GPG2(1)                                                 GNU Privacy Guard                                                GPG2(1)



NAME
       gpg2 - OpenPGP encryption and signing tool

SYNOPSIS
       gpg2 [--homedir dir] [--options file] [options] command [args]


DESCRIPTION
       gpg2  is  the  OpenPGP part of the GNU Privacy Guard (GnuPG). It is a tool to provide digital encryption and signing ser-
       vices using the OpenPGP standard. gpg2 features complete key management and all bells and whistles you can expect from  a
       decent OpenPGP implementation.


       In  contrast  to the standalone version gpg, which is more suited for server and embedded platforms, this version is com-
       monly installed under the name gpg2 and more targeted to  the  desktop  as  it  requires  several  other  modules  to  be
       installed.   The  standalone version will be kept maintained and it is possible to install both versions on the same sys-
       tem.  If you need to use different configuration files, you should make use of something  like  `gpg.conf-2'  instead  of
       just `gpg.conf'.







RETURN VALUE
       The program returns 0 if everything was fine, 1 if at least a signature was bad, and other error codes for fatal errors.


WARNINGS
       Use  a  *good*  password for your user account and a *good* passphrase to protect your secret key. This passphrase is the
       weakest part of the whole system. Programs to do dictionary attacks on your secret keyring are very easy to write and  so
       you should protect your "~/.gnupg/" directory very well.

       Keep in mind that, if this program is used over a network (telnet), it is *very* easy to spy out your passphrase!

       If  you are going to verify detached signatures, make sure that the program knows about it; either give both filenames on
       the command line or use '-' to specify STDIN.


INTEROPERABILITY
       GnuPG tries to be a very flexible implementation of the OpenPGP standard. In particular, GnuPG  implements  many  of  the
       optional  parts of the standard, such as the SHA-512 hash, and the ZLIB and BZIP2 compression algorithms. It is important
       to be aware that not all OpenPGP programs implement these optional algorithms and that  by  forcing  their  use  via  the
       --cipher-algo,  --digest-algo,  --cert-digest-algo,  or --compress-algo options in GnuPG, it is possible to create a per-
       fectly valid OpenPGP message, but one that cannot be read by the intended recipient.

       There are dozens of variations of OpenPGP programs available, and each supports a  slightly  different  subset  of  these
       optional  algorithms.  For example, until recently, no (unhacked) version of PGP supported the BLOWFISH cipher algorithm.
       A message using BLOWFISH simply could not be read by a PGP user. By default, GnuPG uses the standard OpenPGP  preferences
       system  that  will  always  do the right thing and create messages that are usable by all recipients, regardless of which
       OpenPGP program they use. Only override this safe default if you really know what you are doing.

       If you absolutely must override the safe default, or if the preferences on a given key are invalid for some  reason,  you
       are  far better off using the --pgp6, --pgp7, or --pgp8 options. These options are safe as they do not force any particu-
       lar algorithms in violation of OpenPGP, but rather reduce the available algorithms to a "PGP-safe" list.


COMMANDS
       Commands are not distinguished from options except for the fact that only one command is allowed.

       gpg2 may be run with no commands, in which case it will perform a reasonable action depending on the type of file  it  is
       given as input (an encrypted message is decrypted, a signature is verified, a file containing keys is listed).

       Please  remember  that option as well as command parsing stops as soon as a non-option is encountered, you can explicitly
       stop parsing by using the special option --.






   Commands not specific to the function



       --version
              Print the program version and licensing information.  Note that you cannot abbreviate this command.


       --help

       -h     Print a usage message summarizing the most useful command line options.  Note that you cannot abbreviate this com-
              mand.


       --warranty
              Print warranty information.


       --dump-options
              Print a list of all available options and commands.  Note that you cannot abbreviate this command.




   Commands to select the type of operation





       --sign

       -s     Make  a  signature.  This command may be combined with --encrypt (for a signed and encrypted message), --symmetric
              (for a signed and symmetrically encrypted message), or --encrypt and --symmetric together (for  a  signed  message
              that  may  be decrypted via a secret key or a passphrase).  The key to be used for signing is chosen by default or
              can be set with the --local-user and --default-key options.


       --clearsign
              Make a clear text signature.  The content in a clear text signature is  readable  without  any  special  software.
              OpenPGP  software is only needed to verify the signature.  Clear text signatures may modify end-of-line whitespace
              for platform independence and are not intended to be reversible.  The key to be used  for  signing  is  chosen  by
              default or can be set with the --local-user and --default-key options.



       --detach-sign

       -b     Make a detached signature.


       --encrypt

       -e     Encrypt  data.  This  option  may be combined with --sign (for a signed and encrypted message), --symmetric (for a
              message that may be decrypted via a secret key or a passphrase), or --sign and --symmetric together (for a  signed
              message that may be decrypted via a secret key or a passphrase).


       --symmetric

       -c     Encrypt  with a symmetric cipher using a passphrase. The default symmetric cipher used is CAST5, but may be chosen
              with the --cipher-algo option. This option may be combined with --sign (for a signed and  symmetrically  encrypted
              message),  --encrypt  (for  a  message  that  may  be  decrypted  via a secret key or a passphrase), or --sign and
              --encrypt together (for a signed message that may be decrypted via a secret key or a passphrase).


       --store
              Store only (make a simple RFC1991 literal data packet).


       --decrypt

       -d     Decrypt the file given on the command line (or STDIN if no file is specified) and write it to STDOUT (or the  file
              specified  with  --output).  If the decrypted file is signed, the signature is also verified. This command differs
              from the default operation, as it never writes to the filename which is included in the file and it rejects  files
              which don't begin with an encrypted message.


       --verify
              Assume  that the first argument is a signed file or a detached signature and verify it without generating any out-
              put. With no arguments, the signature packet is read from STDIN. If only a sigfile is given, it may be a  complete
              signature  or  a  detached  signature,  in which case the signed stuff is expected in a file without the ".sig" or
              ".asc" extension.  With more than 1 argument, the first should be a detached signature and the remaining files are
              the  signed  stuff.  To  read the signed stuff from STDIN, use '-' as the second filename.  For security reasons a
              detached signature cannot read the signed material from STDIN without denoting it in the above way.


       --multifile
              This modifies certain other commands to accept multiple files for processing on the  command  line  or  read  from
              STDIN  with  each filename on a separate line. This allows for many files to be processed at once. --multifile may
              currently be used along with --verify, --encrypt, and --decrypt. Note that --multifile --verify may  not  be  used
              with detached signatures.


       --verify-files
              Identical to --multifile --verify.


       --encrypt-files
              Identical to --multifile --encrypt.


       --decrypt-files
              Identical to --multifile --decrypt.


       --list-keys

       -k

       --list-public-keys
              List all keys from the public keyrings, or just the keys given on the command line.

              Avoid  using  the  output of this command in scripts or other programs as it is likely to change as GnuPG changes.
              See --with-colons for a machine-parseable key listing command that is appropriate for use  in  scripts  and  other
              programs.


       --list-secret-keys

       -K     List  all  keys  from  the  secret keyrings, or just the ones given on the command line. A # after the letters sec
              means that the secret key is not usable (for example, if it was created via --export-secret-subkeys).


       --list-sigs
              Same as --list-keys, but the signatures are listed too.  This command has the same  effect  as  using  --list-keys
              with --with-sig-list.

              For each signature listed, there are several flags in between the "sig" tag and keyid. These flags give additional
              information about each signature. From left to right, they are the numbers 1-3 for certificate  check  level  (see
              --ask-cert-level), "L" for a local or non-exportable signature (see --lsign-key), "R" for a nonRevocable signature
              (see the --edit-key command "nrsign"), "P" for a signature that contains a policy URL (see --cert-policy-url), "N"
              for  a  signature  that  contains  a notation (see --cert-notation), "X" for an eXpired signature (see --ask-cert-
              expire), and the numbers 1-9 or "T" for 10 and above to indicate trust signature levels (see the  --edit-key  com-
              mand "tsign").


       --check-sigs
              Same  as --list-sigs, but the signatures are verified.  Note that for performance reasons the revocation status of
              a signing key is not shown.  This command has the same effect as using --list-keys with --with-sig-check.

              The status of the verification is indicated by a flag directly following the "sig" tag (and thus before the  flags
              described  above  for  --list-sigs).   A  "!"  indicates  that the signature has been successfully verified, a "-"
              denotes a bad signature and a "%" is used if an error occurred while checking the signature (e.g. a non  supported
              algorithm).


       --locate-keys
              Locate the keys given as arguments.  This command basically uses the same algorithm as used when locating keys for
              encryption or signing and may thus be used to see what keys gpg2 might use.  In  particular  external  methods  as
              defined by --auto-key-locate may be used to locate a key.  Only public keys are listed.



       --fingerprint
              List  all  keys  (or the specified ones) along with their fingerprints. This is the same output as --list-keys but
              with the additional output of a line with the fingerprint. May also be combined with --list-sigs or  --check-sigs.
              If this command is given twice, the fingerprints of all secondary keys are listed too.


       --list-packets
              List only the sequence of packets. This is mainly useful for debugging.



       --card-edit
              Present  a  menu to work with a smartcard. The subcommand "help" provides an overview on available commands. For a
              detailed description, please see the Card HOWTO at  http://www.gnupg.org/documentation/howtos.html#GnuPG-cardHOWTO
              .


       --card-status
              Show the content of the smart card.


       --change-pin
              Present  a  menu  to allow changing the PIN of a smartcard. This functionality is also available as the subcommand
              "passwd" with the --card-edit command.


       --delete-key name
              Remove key from the public keyring. In batch mode either --yes is required or the key must be specified by finger-
              print. This is a safeguard against accidental deletion of multiple keys.


       --delete-secret-key name
              Remove key from the secret and public keyring. In batch mode the key must be specified by fingerprint.


       --delete-secret-and-public-key name
              Same  as  --delete-key, but if a secret key exists, it will be removed first. In batch mode the key must be speci-
              fied by fingerprint.


       --export
              Either export all keys from all keyrings (default keyrings and those registered via option --keyring),  or  if  at
              least  one  name is given, those of the given name. The new keyring is written to STDOUT or to the file given with
              option --output. Use together with --armor to mail those keys.


       --send-keys key IDs
              Similar to --export but sends the keys to a keyserver.  Fingerprints may be used instead of key IDs. Option --key-
              server must be used to give the name of this keyserver. Don't send your complete keyring to a keyserver --- select
              only those keys which are new or changed by you.  If no key IDs are given, gpg does nothing.


       --export-secret-keys

       --export-secret-subkeys
              Same as --export, but exports the secret keys instead.  This is normally not very useful and a security risk.  The
              second  form of the command has the special property to render the secret part of the primary key useless; this is
              a GNU extension to OpenPGP and other implementations can not be expected to successfully import such a  key.   See
              the option --simple-sk-checksum if you want to import such an exported key with an older OpenPGP implementation.


       --import

       --fast-import
              Import/merge keys. This adds the given keys to the keyring. The fast version is currently just a synonym.

              There  are  a  few  other options which control how this command works.  Most notable here is the --import-options
              merge-only option which does not insert new keys but does only the merging of new signatures,  user-IDs  and  sub-
              keys.


       --recv-keys key IDs
              Import  the keys with the given key IDs from a keyserver. Option --keyserver must be used to give the name of this
              keyserver.


       --refresh-keys
              Request updates from a keyserver for keys that already exist on the local keyring. This is useful for  updating  a
              key  with  the  latest  signatures, user IDs, etc. Calling this with no arguments will refresh the entire keyring.
              Option --keyserver must be used to give the name of the keyserver for all keys that do  not  have  preferred  key-
              servers set (see --keyserver-options honor-keyserver-url).


       --search-keys names
              Search  the  keyserver for the given names. Multiple names given here will be joined together to create the search
              string for the keyserver.  Option --keyserver must be used to give the name of this  keyserver.   Keyservers  that
              support  different  search methods allow using the syntax specified in "How to specify a user ID" below. Note that
              different keyserver types support different search methods. Currently only LDAP supports them all.


       --fetch-keys URIs
              Retrieve keys located at the specified URIs. Note that different installations of GnuPG may support different pro-
              tocols (HTTP, FTP, LDAP, etc.)


       --update-trustdb
              Do  trust database maintenance. This command iterates over all keys and builds the Web of Trust. This is an inter-
              active command because it may have to ask for the "ownertrust" values for keys. The user has to give an estimation
              of  how  far she trusts the owner of the displayed key to correctly certify (sign) other keys. GnuPG only asks for
              the ownertrust value if it has not yet been assigned to a key. Using the --edit-key menu, the assigned  value  can
              be changed at any time.


       --check-trustdb
              Do  trust  database  maintenance without user interaction. From time to time the trust database must be updated so
              that expired keys or signatures and the resulting changes in the Web of Trust can be tracked. Normally, GnuPG will
              calculate when this is required and do it automatically unless --no-auto-check-trustdb is set. This command can be
              used to force a trust database check at any time. The processing is identical to that of --update-trustdb  but  it
              skips keys with a not yet defined "ownertrust".

              For  use  with cron jobs, this command can be used together with --batch in which case the trust database check is
              done only if a check is needed. To force a run even in batch mode add the option --yes.



       --export-ownertrust
              Send the ownertrust values to STDOUT. This is useful for backup purposes as these values are the only  ones  which
              can't be re-created from a corrupted trustdb.  Example:
                  gpg2 --export-ownertrust > otrust.txt



       --import-ownertrust
              Update  the  trustdb  with  the ownertrust values stored in files (or STDIN if not given); existing values will be
              overwritten.  In case of a severely damaged trustdb and if you have a recent backup of the ownertrust values (e.g.
              in the file `otrust.txt', you may re-create the trustdb using these commands:
                  cd ~/.gnupg
                  rm trustdb.gpg
                  gpg2 --import-ownertrust < otrust.txt



       --rebuild-keydb-caches
              When  updating  from version 1.0.6 to 1.0.7 this command should be used to create signature caches in the keyring.
              It might be handy in other situations too.


       --print-md algo

       --print-mds
              Print message digest of algorithm ALGO for all given files or STDIN.  With the second form (or a deprecated "*" as
              algo) digests for all available algorithms are printed.


       --gen-random 0|1|2 count
              Emit  count  random bytes of the given quality level 0, 1 or 2. If count is not given or zero, an endless sequence
              of random bytes will be emitted.  If used with --armor the output will be base64 encoded.  PLEASE, don't use  this
              command unless you know what you are doing; it may remove precious entropy from the system!


       --gen-prime mode bits
              Use the source, Luke :-). The output format is still subject to change.



       --enarmor

       --dearmor
              Pack  or  unpack an arbitrary input into/from an OpenPGP ASCII armor.  This is a GnuPG extension to OpenPGP and in
              general not very useful.





   How to manage your keys


       This section explains the main commands for key management



       --gen-key
              Generate a new key pair. This command is normally only used interactively.

              There is an experimental feature which allows you to create keys in batch mode. See the file `doc/DETAILS' in  the
              source distribution on how to use this.


       --gen-revoke name
              Generate a revocation certificate for the complete key. To revoke a subkey or a signature, use the --edit command.


       --desig-revoke name
              Generate  a designated revocation certificate for a key. This allows a user (with the permission of the keyholder)
              to revoke someone else's key.



       --edit-key
              Present a menu which enables you to do most of the key management related tasks.  It expects the specification  of
              a key on the command line.



              uid n  Toggle  selection  of  user ID or photographic user ID with index n.  Use * to select all and 0 to deselect
                     all.


              key n  Toggle selection of subkey with index n.  Use * to select all and 0 to deselect all.


              sign   Make a signature on key of user name If the key is not yet signed by the default user (or the  users  given
                     with  -u),  the  program  displays the information of the key again, together with its fingerprint and asks
                     whether it should be signed. This question is repeated for all users specified with -u.


              lsign  Same as "sign" but the signature is marked as non-exportable and will therefore never be  used  by  others.
                     This may be used to make keys valid only in the local environment.


              nrsign Same as "sign" but the signature is marked as non-revocable and can therefore never be revoked.


              tsign  Make a trust signature. This is a signature that combines the notions of certification (like a regular sig-
                     nature), and trust (like the "trust" command). It is generally  only  useful  in  distinct  communities  or
                     groups.

              Note  that  "l" (for local / non-exportable), "nr" (for non-revocable, and "t" (for trust) may be freely mixed and
              prefixed to "sign" to create a signature of any type desired.



              delsig Delete a signature. Note that it is not possible to retract a signature, once it has been send to the  pub-
                     lic (i.e. to a keyserver).  In that case you better use revsig.


              revsig Revoke  a  signature.  For  every  signature which has been generated by one of the secret keys, GnuPG asks
                     whether a revocation certificate should be generated.


              check  Check the signatures on all selected user IDs.


              adduid Create an additional user ID.


              addphoto
                     Create a photographic user ID. This will prompt for a JPEG file that will be embedded  into  the  user  ID.
                     Note  that a very large JPEG will make for a very large key. Also note that some programs will display your
                     JPEG unchanged (GnuPG), and some programs will scale it to fit in a dialog box (PGP).


              showphoto
                     Display the selected photographic user ID.


              deluid Delete a user ID or photographic user ID.  Note that it is not possible to retract a user id, once  it  has
                     been send to the public (i.e. to a keyserver).  In that case you better use revuid.


              revuid Revoke a user ID or photographic user ID.


              primary
                     Flag  the  current user id as the primary one, removes the primary user id flag from all other user ids and
                     sets the timestamp of all affected self-signatures one second ahead. Note that setting a photo user  ID  as
                     primary  makes it primary over other photo user IDs, and setting a regular user ID as primary makes it pri-
                     mary over other regular user IDs.


              keyserver
                     Set a preferred keyserver for the specified user ID(s). This allows other users to know  where  you  prefer
                     they  get your key from. See --keyserver-options honor-keyserver-url for more on how this works.  Setting a
                     value of "none" removes an existing preferred keyserver.


              notation
                     Set a name=value notation for the specified user ID(s). See --cert-notation for more  on  how  this  works.
                     Setting  a value of "none" removes all notations, setting a notation prefixed with a minus sign (-) removes
                     that notation, and setting a notation name (without the =value) prefixed with  a  minus  sign  removes  all
                     notations with that name.


              pref   List  preferences  from  the  selected  user  ID.  This shows the actual preferences, without including any
                     implied preferences.


              showpref
                     More verbose preferences listing for the selected user ID. This shows the preferences in effect by  includ-
                     ing  the  implied  preferences of 3DES (cipher), SHA-1 (digest), and Uncompressed (compression) if they are
                     not already included in the preference list. In addition, the preferred keyserver and  signature  notations
                     (if any) are shown.


              setpref string
                     Set the list of user ID preferences to string for all (or just the selected) user IDs. Calling setpref with
                     no arguments sets the preference list to the default (either  built-in  or  set  via  --default-preference-
                     list), and calling setpref with "none" as the argument sets an empty preference list. Use gpg2 --version to
                     get a list of available algorithms. Note that while you can change the preferences on an attribute user  ID
                     (aka  "photo  ID"), GnuPG does not select keys via attribute user IDs so these preferences will not be used
                     by GnuPG.

                     When setting preferences, you should list the algorithms in the order which you'd like to see them used  by
                     someone  else  when  encrypting a message to your key.  If you don't include 3DES, it will be automatically
                     added at the end.  Note that there are many factors that go into choosing an algorithm (for  example,  your
                     key  may not be the only recipient), and so the remote OpenPGP application being used to send to you may or
                     may not follow your exact chosen order for a given message.  It will, however,  only  choose  an  algorithm
                     that  is  present  on the preference list of every recipient key.  See also the INTEROPERABILITY WITH OTHER
                     OPENPGP PROGRAMS section below.


              addkey Add a subkey to this key.


              addcardkey
                     Generate a subkey on a card and add it to this key.


              keytocard
                     Transfer the selected secret subkey (or the primary key if no subkey has been selected) to a smartcard. The
                     secret  key  in  the keyring will be replaced by a stub if the key could be stored successfully on the card
                     and you use the save command later. Only certain key types may be transferred  to  the  card.  A  sub  menu
                     allows  you to select on what card to store the key. Note that it is not possible to get that key back from
                     the card - if the card gets broken your secret key will be lost unless you have a backup somewhere.


              bkuptocard file
                     Restore the given file to a card. This command may be used to restore a backup  key  (as  generated  during
                     card  initialization)  to  a  new card. In almost all cases this will be the encryption key. You should use
                     this command only with the corresponding public key and make sure that the file given as argument is indeed
                     the  backup  to restore. You should then select 2 to restore as encryption key.  You will first be asked to
                     enter the passphrase of the backup key and then for the Admin PIN of the card.


              delkey Remove a subkey (secondart key). Note that it is not possible to retract a subkey, once it has been send to
                     the public (i.e. to a keyserver).  In that case you better use revkey.


              revkey Revoke a subkey.


              expire Change  the key or subkey expiration time. If a subkey is selected, the expiration time of this subkey will
                     be changed. With no selection, the key expiration of the primary key is changed.


              trust  Change the owner trust value for the key. This updates the trust-db immediately and no save is required.


              disable

              enable Disable or enable an entire key. A disabled key can not normally be used for encryption.


              addrevoker
                     Add a designated revoker to the key. This takes one optional argument: "sensitive". If a designated revoker
                     is marked as sensitive, it will not be exported by default (see export-options).


              passwd Change the passphrase of the secret key.


              toggle Toggle between public and secret key listing.


              clean  Compact (by removing all signatures except the selfsig) any user ID that is no longer usable (e.g. revoked,
                     or expired). Then, remove any signatures that are not usable by the trust calculations.  Specifically, this
                     removes  any  signature  that  does  not  validate,  any signature that is superseded by a later signature,
                     revoked signatures, and signatures issued by keys that are not present on the keyring.


              minimize
                     Make the key as small as possible. This removes all signatures from each user ID except for the most recent
                     self-signature.


              cross-certify
                     Add cross-certification signatures to signing subkeys that may not currently have them. Cross-certification
                     signatures protect against a subtle attack against signing subkeys. See --require-cross-certification.  All
                     new  keys generated have this signature by default, so this option is only useful to bring older keys up to
                     date.


              save   Save all changes to the key rings and quit.


              quit   Quit the program without updating the key rings.


              The listing shows you the key with its secondary keys and all user ids.  The primary user id  is  indicated  by  a
              dot,  and  selected  keys or user ids are indicated by an asterisk.  The trust value is displayed with the primary
              key: the first is the assigned owner trust and the second is the calculated trust value. Letters are used for  the
              values:



              -      No ownertrust assigned / not yet calculated.


              e      Trust calculation has failed; probably due to an expired key.


              q      Not enough information for calculation.


              n      Never trust this key.


              m      Marginally trusted.


              f      Fully trusted.


              u      Ultimately trusted.


       --sign-key name
              Signs a public key with your secret key. This is a shortcut version of the subcommand "sign" from --edit.


       --lsign-key name
              Signs  a public key with your secret key but marks it as non-exportable. This is a shortcut version of the subcom-
              mand "lsign" from --edit-key.


       --passwd user_id
              Change the passphrase of the secret key belonging to the certificate specified as user_id.  This is a shortcut for
              the sub-command passwd of the edit key menu.





OPTIONS
       gpg2 features a bunch of options to control the exact behaviour and to change the default configuration.


       Long options can be put in an options file (default "~/.gnupg/gpg.conf"). Short option names will not work - for example,
       "armor" is a valid option for the options file, while "a" is not. Do not write the 2 dashes, but simply the name  of  the
       option  and  any required arguments. Lines with a hash ('#') as the first non-white-space character are ignored. Commands
       may be put in this file too, but that is not generally useful as the command will execute automatically with every execu-
       tion of gpg.

       Please  remember  that  option  parsing  stops as soon as a non-option is encountered, you can explicitly stop parsing by
       using the special option --.



   How to change the configuration


       These options are used to change the configuration and are usually found in the option file.



       --default-key name
              Use name as the default key to sign with. If this option is not used, the default key is the first  key  found  in
              the secret keyring.  Note that -u or --local-user overrides this option.


       --default-recipient name
              Use name as default recipient if option --recipient is not used and don't ask if this is a valid one. name must be
              non-empty.


       --default-recipient-self
              Use the default key as default recipient if option --recipient is not used and don't ask if this is a  valid  one.
              The default key is the first one from the secret keyring or the one set with --default-key.


       --no-default-recipient
              Reset --default-recipient and --default-recipient-self.


       -v, --verbose
              Give more information during processing. If used twice, the input data is listed in detail.


       --no-verbose
              Reset verbose level to 0.


       -q, --quiet
              Try to be as quiet as possible.


       --batch

       --no-batch
              Use  batch  mode.  Never ask, do not allow interactive commands.  --no-batch disables this option.  Note that even
              with a filename given on the command line, gpg might still need to read from STDIN (in particular if  gpg  figures
              that the input is a detached signature and no data file has been specified).  Thus if you do not want to feed data
              via STDIN, you should connect STDIN to `/dev/null'.


       --no-tty
              Make sure that the TTY (terminal) is never used for any output.  This option is needed in some cases because GnuPG
              sometimes prints warnings to the TTY even if --batch is used.


       --yes  Assume "yes" on most questions.


       --no   Assume "no" on most questions.



       --list-options parameters
              This  is  a  space  or  comma  delimited string that gives options used when listing keys and signatures (that is,
              --list-keys, --list-sigs, --list-public-keys, --list-secret-keys, and the --edit-key functions).  Options  can  be
              prepended with a no- (after the two dashes) to give the opposite meaning.  The options are:



              show-photos
                     Causes  --list-keys,  --list-sigs,  --list-public-keys,  and  --list-secret-keys  to  display any photo IDs
                     attached to the key.  Defaults to no. See also --photo-viewer.   Does  not  work  with  --with-colons:  see
                     --attribute-fd for the appropriate way to get photo data for scripts and other frontends.


              show-policy-urls
                     Show policy URLs in the --list-sigs or --check-sigs listings.  Defaults to no.


              show-notations

              show-std-notations

              show-user-notations
                     Show  all,  IETF standard, or user-defined signature notations in the --list-sigs or --check-sigs listings.
                     Defaults to no.


              show-keyserver-urls

                     Show any preferred keyserver URL in the --list-sigs or --check-sigs listings. Defaults to no.


              show-uid-validity
                     Display the calculated validity of user IDs during key listings.  Defaults to no.


              show-unusable-uids
                     Show revoked and expired user IDs in key listings. Defaults to no.


              show-unusable-subkeys
                     Show revoked and expired subkeys in key listings. Defaults to no.


              show-keyring
                     Display the keyring name at the head of key listings to show which keyring a given key resides on. Defaults
                     to no.


              show-sig-expire
                     Show signature expiration dates (if any) during --list-sigs or --check-sigs listings. Defaults to no.


              show-sig-subpackets
                     Include signature subpackets in the key listing. This option can take an optional argument list of the sub-
                     packets to list. If no argument is passed, list all subpackets. Defaults to no. This option is  only  mean-
                     ingful when using --with-colons along with --list-sigs or --check-sigs.


       --verify-options parameters
              This  is  a  space  or  comma  delimited  string that gives options used when verifying signatures. Options can be
              prepended with a `no-' to give the opposite meaning. The options are:



              show-photos
                     Display any photo IDs present on the key that issued the signature.  Defaults  to  no.  See  also  --photo-
                     viewer.


              show-policy-urls
                     Show policy URLs in the signature being verified. Defaults to no.


              show-notations

              show-std-notations

              show-user-notations
                     Show  all,  IETF standard, or user-defined signature notations in the signature being verified. Defaults to
                     IETF standard.


              show-keyserver-urls
                     Show any preferred keyserver URL in the signature being verified.  Defaults to no.


              show-uid-validity
                     Display the calculated validity of the user IDs on the key that issued the signature. Defaults to no.


              show-unusable-uids
                     Show revoked and expired user IDs during signature verification.  Defaults to no.


              show-primary-uid-only
                     Show only the primary user ID during signature verification.  That is all the AKA lines as  well  as  photo
                     Ids are not shown with the signature verification status.


              pka-lookups
                     Enable  PKA  lookups to verify sender addresses. Note that PKA is based on DNS, and so enabling this option
                     may disclose information on when and what signatures are verified or to whom data  is  encrypted.  This  is
                     similar to the "web bug" described for the auto-key-retrieve feature.


              pka-trust-increase
                     Raise the trust in a signature to full if the signature passes PKA validation. This option is only meaning-
                     ful if pka-lookups is set.


       --enable-dsa2

       --disable-dsa2
              Enable hash truncation for all DSA keys even for old DSA Keys up to 1024 bit.   This  is  also  the  default  with
              --openpgp.   Note  that older versions of GnuPG also required this flag to allow the generation of DSA larger than
              1024 bit.


       --photo-viewer string
              This is the command line that should be run to view a photo ID. "%i" will be expanded to a filename containing the
              photo.  "%I"  does  the same, except the file will not be deleted once the viewer exits.  Other flags are "%k" for
              the key ID, "%K" for the long key ID, "%f" for the key fingerprint, "%t" for the extension of the image type (e.g.
              "jpg"), "%T" for the MIME type of the image (e.g. "image/jpeg"), "%v" for the single-character calculated validity
              of the image being viewed (e.g. "f"), "%V" for the calculated validity as a string (e.g.  "full"), and "%%" for an
              actual  percent  sign.  If neither %i or %I are present, then the photo will be supplied to the viewer on standard
              input.

              The default viewer is "xloadimage -fork -quiet -title 'KeyID 0x%k' STDIN". Note that if your image viewer  program
              is not secure, then executing it from GnuPG does not make it secure.


       --exec-path string
              Sets  a  list of directories to search for photo viewers and keyserver helpers. If not provided, keyserver helpers
              use the compiled-in default directory, and photo viewers use the $PATH environment variable.  Note,  that  on  W32
              system this value is ignored when searching for keyserver helpers.


       --keyring file
              Add file to the current list of keyrings. If file begins with a tilde and a slash, these are replaced by the $HOME
              directory. If the filename does not contain a slash, it is assumed to be in the GnuPG home  directory  ("~/.gnupg"
              if --homedir or $GNUPGHOME is not used).

              Note  that  this  adds  a  keyring  to  the current list. If the intent is to use the specified keyring alone, use
              --keyring along with --no-default-keyring.


       --secret-keyring file
              Same as --keyring but for the secret keyrings.


       --primary-keyring file
              Designate file as the primary public keyring. This means that newly  imported  keys  (via  --import  or  keyserver
              --recv-from) will go to this keyring.


       --trustdb-name file
              Use  file instead of the default trustdb. If file begins with a tilde and a slash, these are replaced by the $HOME
              directory. If the filename does not contain a slash, it is assumed to be in the GnuPG home  directory  (`~/.gnupg'
              if --homedir or $GNUPGHOME is not used).


       --homedir dir
              Set  the name of the home directory to dir. If this option is not used, the home directory defaults to `~/.gnupg'.
              It is only recognized when given on the command line.  It also overrides any home  directory  stated  through  the
              environment  variable `GNUPGHOME' or (on W32 systems) by means of the Registry entry HKCU\Software\GNU\GnuPG:Home-
              Dir.







       --display-charset name
              Set the name of the native character set. This is used to convert some informational strings like user IDs to  the
              proper UTF-8 encoding.  Note that this has nothing to do with the character set of data to be encrypted or signed;
              GnuPG does not recode user-supplied data. If this option is not used, the default character set is determined from
              the current locale. A verbosity level of 3 shows the chosen set.  Valid values for name are:



              iso-8859-1
                     This is the Latin 1 set.


              iso-8859-2
                     The Latin 2 set.


              iso-8859-15
                     This is currently an alias for the Latin 1 set.


              koi8-r The usual Russian set (rfc1489).


              utf-8  Bypass all translations and assume that the OS uses native UTF-8 encoding.


       --utf8-strings

       --no-utf8-strings
              Assume  that  command  line arguments are given as UTF8 strings. The default (--no-utf8-strings) is to assume that
              arguments are encoded in the character set as specified by --display-charset. These options affect  all  following
              arguments. Both options may be used multiple times.


       --options file
              Read  options  from file and do not try to read them from the default options file in the homedir (see --homedir).
              This option is ignored if used in an options file.


       --no-options
              Shortcut for --options /dev/null. This option is detected before an attempt to open an option  file.   Using  this
              option will also prevent the creation of a `~/.gnupg' homedir.




       -z n

       --compress-level n

       --bzip2-compress-level n
              Set compression level to n for the ZIP and ZLIB compression algorithms. The default is to use the default compres-
              sion level of zlib (normally 6). --bzip2-compress-level sets the compression level for the BZIP2 compression algo-
              rithm  (defaulting  to 6 as well). This is a different option from --compress-level since BZIP2 uses a significant
              amount of memory for each additional compression level.  -z sets both. A value of 0 for n disables compression.


       --bzip2-decompress-lowmem
              Use a different decompression method for BZIP2 compressed files. This alternate method uses a bit more  than  half
              the  memory,  but also runs at half the speed. This is useful under extreme low memory circumstances when the file
              was originally compressed at a high --bzip2-compress-level.



       --mangle-dos-filenames

       --no-mangle-dos-filenames
              Older version of Windows cannot handle filenames with more than one dot. --mangle-dos-filenames  causes  GnuPG  to
              replace  (rather  than  add  to)  the extension of an output filename to avoid this problem. This option is off by
              default and has no effect on non-Windows platforms.


       --ask-cert-level

       --no-ask-cert-level
              When making a key signature, prompt for a certification level. If this option is not specified, the  certification
              level  used  is  set via --default-cert-level. See --default-cert-level for information on the specific levels and
              how they are used. --no-ask-cert-level disables this option. This option defaults to no.


       --default-cert-level n
              The default to use for the check level when signing a key.

              0 means you make no particular claim as to how carefully you verified the key.

              1 means you believe the key is owned by the person who claims to own it but you could not, or did not  verify  the
              key at all. This is useful for a "persona" verification, where you sign the key of a pseudonymous user.

              2  means  you did casual verification of the key. For example, this could mean that you verified that the key fin-
              gerprint and checked the user ID on the key against a photo ID.

              3 means you did extensive verification of the key. For example, this could mean that you verified the key  finger-
              print with the owner of the key in person, and that you checked, by means of a hard to forge document with a photo
              ID (such as a passport) that the name of the key owner matches the name in the user ID on  the  key,  and  finally
              that you verified (by exchange of email) that the email address on the key belongs to the key owner.

              Note  that  the  examples  given  above for levels 2 and 3 are just that: examples. In the end, it is up to you to
              decide just what "casual" and "extensive" mean to you.

              This option defaults to 0 (no particular claim).


       --min-cert-level
              When building the trust database, treat any signatures with a certification level below this as invalid.  Defaults
              to 2, which disregards level 1 signatures. Note that level 0 "no particular claim" signatures are always accepted.


       --trusted-key long key ID
              Assume  that  the specified key (which must be given as a full 8 byte key ID) is as trustworthy as one of your own
              secret keys. This option is useful if you don't want to keep your secret keys (or one of them)  online  but  still
              want to be able to check the validity of a given recipient's or signator's key.


       --trust-model pgp|classic|direct|always|auto
              Set what trust model GnuPG should follow. The models are:



              pgp    This  is  the Web of Trust combined with trust signatures as used in PGP 5.x and later. This is the default
                     trust model when creating a new trust database.


              classic
                     This is the standard Web of Trust as used in PGP 2.x and earlier.


              direct Key validity is set directly by the user and not calculated via the Web of Trust.


              always Skip key validation and assume that used keys are always fully trusted. You generally won't use this unless
                     you  are  using  some external validation scheme. This option also suppresses the "[uncertain]" tag printed
                     with signature checks when there is no evidence that the user ID is bound to the key.


              auto   Select the trust model depending on whatever the internal trust database says. This is the default model if
                     such a database already exists.


       --auto-key-locate parameters

       --no-auto-key-locate
              GnuPG  can  automatically locate and retrieve keys as needed using this option. This happens when encrypting to an
              email address (in the "userATexample.com" form), and there are no userATexample.com keys on the local keyring.  This
              option takes any number of the following mechanisms, in the order they are to be tried:



              cert   Locate a key using DNS CERT, as specified in rfc4398.


              pka    Locate a key using DNS PKA.


              ldap   Using  DNS  Service Discovery, check the domain in question for any LDAP keyservers to use.  If this fails,
                     attempt to locate the key using the PGP Universal method of checking 'ldap://keys.(thedomain)'.


              keyserver
                     Locate a key using whatever keyserver is defined using the --keyserver option.


              keyserver-URL
                     In addition, a keyserver URL as used in the --keyserver option may be used here to  query  that  particular
                     keyserver.


              local  Locate  the  key using the local keyrings.  This mechanism allows to select the order a local key lookup is
                     done.  Thus using '--auto-key-locate local' is identical to --no-auto-key-locate.


              nodefault
                     This flag disables the standard local key lookup, done before any of the mechanisms defined by the  --auto-
                     key-locate  are  tried.  The position of this mechanism in the list does not matter.  It is not required if
                     local is also used.



       --keyid-format short|0xshort|long|0xlong
              Select how to display key IDs. "short" is the traditional 8-character key ID. "long" is  the  more  accurate  (but
              less  convenient) 16-character key ID. Add an "0x" to either to include an "0x" at the beginning of the key ID, as
              in 0x99242560.  Note that this option is ignored if the option --with-colons is used.


       --keyserver name
              Use name as your keyserver. This is the server that --recv-keys, --send-keys, and --search-keys  will  communicate
              with to receive keys from, send keys to, and search for keys on. The format of the name is a URI: `scheme:[//]key-
              servername[:port]' The scheme is the type of keyserver: "hkp" for the HTTP (or compatible) keyservers, "ldap"  for
              the  LDAP  keyservers,  or "mailto" for the Graff email keyserver. Note that your particular installation of GnuPG
              may have other keyserver types available as well. Keyserver schemes  are  case-insensitive.  After  the  keyserver
              name,  optional  keyserver  configuration  options  may be provided. These are the same as the global --keyserver-
              options from below, but apply only to this particular keyserver.

              Most keyservers synchronize with each other, so there is generally no need to send keys to more than  one  server.
              The keyserver hkp://keys.gnupg.net uses round robin DNS to give a different keyserver each time you use it.


       --keyserver-options name=value1
              This  is  a  space  or comma delimited string that gives options for the keyserver. Options can be prefixed with a
              `no-' to give the opposite meaning. Valid import-options or export-options may be used here as well  to  apply  to
              importing  (--recv-key)  or exporting (--send-key) a key from a keyserver. While not all options are available for
              all keyserver types, some common options are:



              include-revoked
                     When searching for a key with --search-keys, include keys that are marked on the keyserver as revoked. Note
                     that  not  all  keyservers  differentiate  between revoked and unrevoked keys, and for such keyservers this
                     option is meaningless. Note also that most keyservers do not have cryptographic verification of key revoca-
                     tions, and so turning this option off may result in skipping keys that are incorrectly marked as revoked.


              include-disabled
                     When  searching  for  a  key with --search-keys, include keys that are marked on the keyserver as disabled.
                     Note that this option is not used with HKP keyservers.


              auto-key-retrieve
                     This option enables the automatic retrieving of keys from a keyserver when  verifying  signatures  made  by
                     keys that are not on the local keyring.

                     Note that this option makes a "web bug" like behavior possible.  Keyserver operators can see which keys you
                     request, so by sending you a message signed by a brand new key (which you naturally will not have  on  your
                     local keyring), the operator can tell both your IP address and the time when you verified the signature.


              honor-keyserver-url
                     When  using  --refresh-keys,  if the key in question has a preferred keyserver URL, then use that preferred
                     keyserver to refresh the key from. In addition, if auto-key-retrieve is set, and the signature being  veri-
                     fied  has  a  preferred keyserver URL, then use that preferred keyserver to fetch the key from. Defaults to
                     yes.


              honor-pka-record
                     If auto-key-retrieve is set, and the signature being verified has a PKA record, then use the  PKA  informa-
                     tion to fetch the key. Defaults to yes.


              include-subkeys
                     When receiving a key, include subkeys as potential targets. Note that this option is not used with HKP key-
                     servers, as they do not support retrieving keys by subkey id.


              use-temp-files
                     On most Unix-like platforms, GnuPG communicates with the keyserver helper program via pipes, which  is  the
                     most  efficient  method.  This option forces GnuPG to use temporary files to communicate. On some platforms
                     (such as Win32 and RISC OS), this option is always enabled.


              keep-temp-files
                     If using `use-temp-files', do not delete the temp files after using them. This option is  useful  to  learn
                     the keyserver communication protocol by reading the temporary files.


              verbose
                     Tell  the  keyserver  helper  program  to  be  more  verbose. This option can be repeated multiple times to
                     increase the verbosity level.


              timeout
                     Tell the keyserver helper program how long (in seconds) to try and perform a keyserver action before giving
                     up.  Note  that performing multiple actions at the same time uses this timeout value per action.  For exam-
                     ple, when retrieving multiple keys via --recv-keys, the timeout applies separately to each  key  retrieval,
                     and not to the --recv-keys command as a whole. Defaults to 30 seconds.


              http-proxy=value
                     Set the proxy to use for HTTP and HKP keyservers.  This overrides the "http_proxy" environment variable, if
                     any.


              max-cert-size
                     When retrieving a key via DNS CERT, only accept keys up to this size.  Defaults to 16384 bytes.


              debug  Turn on debug output in the keyserver helper program.  Note that the details of  debug  output  depends  on
                     which  keyserver helper program is being used, and in turn, on any libraries that the keyserver helper pro-
                     gram uses internally (libcurl, openldap, etc).


              check-cert
                     Enable certificate checking if the keyserver presents one (for hkps or ldaps).  Defaults to on.


              ca-cert-file
                     Provide a certificate store to override the system default.  Only necessary if check-cert is  enabled,  and
                     the keyserver is using a certificate that is not present in a system default certificate list.

                     Note  that  depending  on  the  SSL library that the keyserver helper is built with, this may actually be a
                     directory or a file.


       --completes-needed n
              Number of completely trusted users to introduce a new key signer (defaults to 1).


       --marginals-needed n
              Number of marginally trusted users to introduce a new key signer (defaults to 3)


       --max-cert-depth n
              Maximum depth of a certification chain (default is 5).


       --simple-sk-checksum
              Secret keys are integrity protected by using a SHA-1 checksum. This  method  is  part  of  the  upcoming  enhanced
              OpenPGP  specification  but  GnuPG  already uses it as a countermeasure against certain attacks.  Old applications
              don't understand this new format, so this option may be used to switch back  to  the  old  behaviour.  Using  this
              option bears a security risk. Note that using this option only takes effect when the secret key is encrypted - the
              simplest way to make this happen is to change the passphrase on the key (even changing it to  the  same  value  is
              acceptable).


       --no-sig-cache
              Do  not cache the verification status of key signatures.  Caching gives a much better performance in key listings.
              However, if you suspect that your public keyring is not save against write modifications, you can use this  option
              to  disable  the  caching. It probably does not make sense to disable it because all kind of damage can be done if
              someone else has write access to your public keyring.


       --no-sig-create-check
              GnuPG normally verifies each signature right after creation to protect  against  bugs  and  hardware  malfunctions
              which  could leak out bits from the secret key. This extra verification needs some time (about 115% for DSA keys),
              and so this option can be used to disable it.  However, due to the fact that the signature creation  needs  manual
              interaction, this performance penalty does not matter in most settings.


       --auto-check-trustdb

       --no-auto-check-trustdb
              If  GnuPG  feels that its information about the Web of Trust has to be updated, it automatically runs the --check-
              trustdb command internally.  This may be a time consuming process. --no-auto-check-trustdb disables this option.


       --use-agent

       --no-use-agent
              This is dummy option. gpg2 always requires the agent.


       --gpg-agent-info
              This is dummy option. It has no effect when used with gpg2.


       --lock-once
              Lock the databases the first time a lock is requested and do not release the lock until the process terminates.


       --lock-multiple
              Release the locks every time a lock is no longer needed. Use this to override a previous --lock-once from a config
              file.


       --lock-never
              Disable  locking  entirely.  This option should be used only in very special environments, where it can be assured
              that only one process is accessing those files. A bootable floppy with a stand-alone encryption system will proba-
              bly use this. Improper usage of this option may lead to data and key corruption.


       --exit-on-status-write-error
              This  option will cause write errors on the status FD to immediately terminate the process. That should in fact be
              the default but it never worked this way and thus we need an option to enable this, so that the change won't break
              applications which close their end of a status fd connected pipe too early. Using this option along with --enable-
              progress-filter may be used to cleanly cancel long running gpg operations.


       --limit-card-insert-tries n
              With n greater than 0 the number of prompts asking to insert a smartcard gets limited to N-1. Thus with a value of
              1 gpg won't at all ask to insert a card if none has been inserted at startup. This option is useful in the config-
              uration file in case an application does not know about the smartcard  support  and  waits  ad  infinitum  for  an
              inserted card.


       --no-random-seed-file
              GnuPG  uses  a file to store its internal random pool over invocations.  This makes random generation faster; how-
              ever sometimes write operations are not desired. This option can be used to achieve that with the cost  of  slower
              random generation.


       --no-greeting
              Suppress the initial copyright message.


       --no-secmem-warning
              Suppress the warning about "using insecure memory".


       --no-permission-warning
              Suppress the warning about unsafe file and home directory (--homedir) permissions. Note that the permission checks
              that GnuPG performs are not intended to be authoritative, but rather they simply warn about certain common permis-
              sion problems. Do not assume that the lack of a warning means that your system is secure.

              Note  that  the  warning for unsafe --homedir permissions cannot be suppressed in the gpg.conf file, as this would
              allow an attacker to place an unsafe gpg.conf file in place, and use this file to suppress warnings about  itself.
              The --homedir permissions warning may only be suppressed on the command line.


       --no-mdc-warning
              Suppress the warning about missing MDC integrity protection.


       --require-secmem

       --no-require-secmem
              Refuse to run if GnuPG cannot get secure memory. Defaults to no (i.e. run, but give a warning).



       --require-cross-certification

       --no-require-cross-certification
              When  verifying a signature made from a subkey, ensure that the cross certification "back signature" on the subkey
              is present and valid.  This protects against  a  subtle  attack  against  subkeys  that  can  sign.   Defaults  to
              --require-cross-certification for gpg2.


       --expert

       --no-expert
              Allow  the  user  to  do  certain nonsensical or "silly" things like signing an expired or revoked key, or certain
              potentially incompatible things like generating unusual key types. This also  disables  certain  warning  messages
              about  potentially  incompatible actions. As the name implies, this option is for experts only. If you don't fully
              understand the implications of what it allows you to do, leave this off. --no-expert disables this option.








   Key related options




       --recipient name

       -r     Encrypt for user id name. If this option or --hidden-recipient is not specified, GnuPG asks for the user-id unless
              --default-recipient is given.


       --hidden-recipient name

       -R     Encrypt  for  user  ID name, but hide the key ID of this user's key. This option helps to hide the receiver of the
              message and is a limited countermeasure against traffic analysis. If this option or --recipient is not  specified,
              GnuPG asks for the user ID unless --default-recipient is given.


       --encrypt-to name
              Same  as --recipient but this one is intended for use in the options file and may be used with your own user-id as
              an "encrypt-to-self". These keys are only used when there are other recipients given either by use of  --recipient
              or by the asked user id.  No trust checking is performed for these user ids and even disabled keys can be used.


       --hidden-encrypt-to name
              Same  as  --hidden-recipient  but  this  one is intended for use in the options file and may be used with your own
              user-id as a hidden "encrypt-to-self". These keys are only used when there are other recipients  given  either  by
              use  of  --recipient or by the asked user id.  No trust checking is performed for these user ids and even disabled
              keys can be used.


       --no-encrypt-to
              Disable the use of all --encrypt-to and --hidden-encrypt-to keys.


       --group name=value1
              Sets up a named group, which is similar to aliases in email programs.  Any time the group name is a recipient  (-r
              or --recipient), it will be expanded to the values specified. Multiple groups with the same name are automatically
              merged into a single group.

              The values are key IDs or fingerprints, but any key description is accepted. Note that a value with spaces  in  it
              will  be  treated  as  two different values. Note also there is only one level of expansion --- you cannot make an
              group that points to another group. When used from the command line, it may be necessary to quote the argument  to
              this option to prevent the shell from treating it as multiple arguments.


       --ungroup name
              Remove a given entry from the --group list.


       --no-groups
              Remove all entries from the --group list.


       --local-user name

       -u     Use name as the key to sign with. Note that this option overrides --default-key.


       --try-secret-key name
              For  hidden  recipients GPG needs to know the keys to use for trial decryption.  The key set with --default-key is
              always tried first, but this is often not sufficient.  This option allows to set more keys to be  used  for  trial
              decryption.  Although any valid user-id specification may be used for name it makes sense to use at least the long
              keyid to avoid ambiguities.  Note that gpg-agent might pop up a pinentry for a lot keys to do  the  trial  decryp-
              tion.  If you want to stop all further trial decryption you may use close-window button instead of the cancel but-
              ton.


       --try-all-secrets
              Don't look at the key ID as stored in the message but try all secret keys in turn to  find  the  right  decryption
              key.  This  option forces the behaviour as used by anonymous recipients (created by using --throw-keyids or --hid-
              den-recipient) and might come handy in case where an encrypted message contains a bogus key ID.


       --skip-hidden-recipients

       --no-skip-hidden-recipients
              During decryption skip all anonymous recipients.  This option helps in the case that people use the hidden recipi-
              ents  feature  to  hide  there own encrypt-to key from others.  If oneself has many secret keys this may lead to a
              major annoyance because all keys are tried in turn to decrypt soemthing which was not really intended for it.  The
              drawback  of  this  option is that it is currently not possible to decrypt a message which includes real anonymous
              recipients.





   Input and Output




       --armor

       -a     Create ASCII armored output.  The default is to create the binary OpenPGP format.


       --no-armor
              Assume the input data is not in ASCII armored format.


       --output file

       -o file
              Write output to file.


       --max-output n
              This option sets a limit on the number of bytes that will be generated when processing a file. Since OpenPGP  sup-
              ports  various  levels  of  compression, it is possible that the plaintext of a given message may be significantly
              larger than the original OpenPGP message. While GnuPG works properly with such messages, there is often  a  desire
              to  set  a maximum file size that will be generated before processing is forced to stop by the OS limits. Defaults
              to 0, which means "no limit".


       --import-options parameters
              This is a space or comma delimited string that gives options for importing keys. Options can be prepended  with  a
              `no-' to give the opposite meaning. The options are:



              import-local-sigs
                     Allow  importing  key  signatures  marked  as "local". This is not generally useful unless a shared keyring
                     scheme is being used.  Defaults to no.


              repair-pks-subkey-bug
                     During import, attempt to repair the damage caused by the PKS keyserver bug (pre version 0.9.6)  that  man-
                     gles  keys  with  multiple subkeys. Note that this cannot completely repair the damaged key as some crucial
                     data is removed by the keyserver, but it does at least give you back one subkey. Defaults to no for regular
                     --import and to yes for keyserver --recv-keys.


              merge-only
                     During  import,  allow key updates to existing keys, but do not allow any new keys to be imported. Defaults
                     to no.


              import-clean
                     After import, compact (remove all signatures except the self-signature) any user IDs from the new key  that
                     are  not  usable.   Then, remove any signatures from the new key that are not usable.  This includes signa-
                     tures that were issued by keys that are not present on the keyring. This option is the same as running  the
                     --edit-key command "clean" after import. Defaults to no.


              import-minimal
                     Import the smallest key possible. This removes all signatures except the most recent self-signature on each
                     user ID. This option is the same as running the --edit-key command "minimize" after  import.   Defaults  to
                     no.


       --export-options parameters
              This  is  a space or comma delimited string that gives options for exporting keys. Options can be prepended with a
              `no-' to give the opposite meaning. The options are:



              export-local-sigs
                     Allow exporting key signatures marked as "local". This is not generally  useful  unless  a  shared  keyring
                     scheme is being used.  Defaults to no.


              export-attributes
                     Include  attribute user IDs (photo IDs) while exporting. This is useful to export keys if they are going to
                     be used by an OpenPGP program that does not accept attribute user IDs. Defaults to yes.


              export-sensitive-revkeys
                     Include designated revoker information that was marked as "sensitive". Defaults to no.


              export-reset-subkey-passwd
                     When using the --export-secret-subkeys command, this option resets the passphrases for all exported subkeys
                     to empty. This is useful when the exported subkey is to be used on an unattended machine where a passphrase
                     doesn't necessarily make sense. Defaults to no.


              export-clean
                     Compact (remove all signatures from) user IDs on the key being exported if the user  IDs  are  not  usable.
                     Also,  do  not export any signatures that are not usable. This includes signatures that were issued by keys
                     that are not present on the keyring. This option is the same as  running  the  --edit-key  command  "clean"
                     before export except that the local copy of the key is not modified. Defaults to no.


              export-minimal
                     Export the smallest key possible. This removes all signatures except the most recent self-signature on each
                     user ID. This option is the same as running the --edit-key command "minimize" before export except that the
                     local copy of the key is not modified. Defaults to no.


       --with-colons
              Print key listings delimited by colons. Note that the output will be encoded in UTF-8 regardless of any --display-
              charset setting. This format is useful when GnuPG is called from scripts  and  other  programs  as  it  is  easily
              machine  parsed.  The  details  of  this format are documented in the file `doc/DETAILS', which is included in the
              GnuPG source distribution.


       --fixed-list-mode
              Do not merge primary user ID and primary key in --with-colon listing mode and  print  all  timestamps  as  seconds
              since 1970-01-01.  Since GnuPG 2.0.10, this mode is always used and thus this option is obsolete; it does not harm
              to use it though.


       --with-fingerprint
              Same as the command --fingerprint but changes only the format of the output and may be used together with  another
              command.


       --with-keygrip
              Include the keygrip in the key listings.




   OpenPGP protocol specific options.




       -t, --textmode

       --no-textmode
              Treat  input  files  as  text and store them in the OpenPGP canonical text form with standard "CRLF" line endings.
              This also sets the necessary flags to inform the recipient that the encrypted or signed data is text and may  need
              its  line  endings  converted  back  to  whatever  the local system uses. This option is useful when communicating
              between two platforms that have different line ending conventions (UNIX-like to Mac, Mac to Windows,  etc).  --no-
              textmode disables this option, and is the default.



       --force-v3-sigs

       --no-force-v3-sigs
              OpenPGP states that an implementation should generate v4 signatures but PGP versions 5 through 7 only recognize v4
              signatures on key material. This option forces v3 signatures for  signatures  on  data.   Note  that  this  option
              implies  --no-ask-sig-expire,  and unsets --sig-policy-url, --sig-notation, and --sig-keyserver-url, as these fea-
              tures cannot be used with v3 signatures.  --no-force-v3-sigs disables this option.  Defaults to no.


       --force-v4-certs

       --no-force-v4-certs
              Always use v4 key signatures even on v3 keys. This option also changes the default hash algorithm for v3 RSA  keys
              from MD5 to SHA-1.  --no-force-v4-certs disables this option.


       --force-mdc
              Force  the use of encryption with a modification detection code. This is always used with the newer ciphers (those
              with a blocksize greater than 64 bits), or if all of the recipient keys indicate  MDC  support  in  their  feature
              flags.


       --disable-mdc
              Disable  the use of the modification detection code. Note that by using this option, the encrypted message becomes
              vulnerable to a message modification attack.


       --personal-cipher-preferences string
              Set the list of personal cipher preferences to string.  Use gpg2 --version to get a list of available  algorithms,
              and  use  none  to  set no preference at all.  This allows the user to safely override the algorithm chosen by the
              recipient key preferences, as GPG will only select an algorithm that is usable by all recipients.  The most highly
              ranked cipher in this list is also used for the --symmetric encryption command.


       --personal-digest-preferences string
              Set  the list of personal digest preferences to string.  Use gpg2 --version to get a list of available algorithms,
              and use none to set no preference at all.  This allows the user to safely override the  algorithm  chosen  by  the
              recipient key preferences, as GPG will only select an algorithm that is usable by all recipients.  The most highly
              ranked digest algorithm in this list is also used when signing without encryption (e.g. --clearsign or --sign).


       --personal-compress-preferences string
              Set the list of personal compression preferences to string.  Use gpg2 --version to get a list of  available  algo-
              rithms, and use none to set no preference at all.  This allows the user to safely override the algorithm chosen by
              the recipient key preferences, as GPG will only select an algorithm that is usable by all  recipients.   The  most
              highly  ranked  compression algorithm in this list is also used when there are no recipient keys to consider (e.g.
              --symmetric).


       --s2k-cipher-algo name
              Use name as the cipher algorithm used to protect secret keys.  The default cipher is CAST5. This  cipher  is  also
              used for conventional encryption if --personal-cipher-preferences and --cipher-algo is not given.


       --s2k-digest-algo name
              Use name as the digest algorithm used to mangle the passphrases.  The default algorithm is SHA-1.


       --s2k-mode n
              Selects  how  passphrases  are  mangled. If n is 0 a plain passphrase (which is not recommended) will be used, a 1
              adds a salt to the passphrase and a 3 (the default) iterates the whole process  a  number  of  times  (see  --s2k-
              count).  Unless --rfc1991 is used, this mode is also used for conventional encryption.


       --s2k-count n
              Specify how many times the passphrase mangling is repeated.  This value may range between 1024 and 65011712 inclu-
              sive, and the default is 65536.  Note that not all values in the 1024-65011712 range are legal and if  an  illegal
              value  is  selected, GnuPG will round up to the nearest legal value.  This option is only meaningful if --s2k-mode
              is 3.





   Compliance options


       These options control what GnuPG is compliant to. Only one of these options may be  active  at  a  time.  Note  that  the
       default  setting  of  this is nearly always the correct one. See the INTEROPERABILITY WITH OTHER OPENPGP PROGRAMS section
       below before using one of these options.



       --gnupg
              Use standard GnuPG behavior. This is essentially OpenPGP behavior (see --openpgp), but with some additional  work-
              arounds  for  common compatibility problems in different versions of PGP. This is the default option, so it is not
              generally needed, but it may be useful to override a different compliance option in the gpg.conf file.


       --openpgp
              Reset all packet, cipher and digest options to strict OpenPGP behavior. Use this  option  to  reset  all  previous
              options  like --s2k-*, --cipher-algo, --digest-algo and --compress-algo to OpenPGP compliant values. All PGP work-
              arounds are disabled.


       --rfc4880
              Reset all packet, cipher and digest options to strict RFC-4880 behavior. Note that  this  is  currently  the  same
              thing as --openpgp.


       --rfc2440
              Reset all packet, cipher and digest options to strict RFC-2440 behavior.


       --rfc1991
              Try to be more RFC-1991 (PGP 2.x) compliant.


       --pgp2 Set  up  all  options to be as PGP 2.x compliant as possible, and warn if an action is taken (e.g. encrypting to a
              non-RSA key) that will create a message that PGP 2.x will not be able to handle. Note that `PGP  2.x'  here  means
              `MIT PGP 2.6.2'. There are other versions of PGP 2.x available, but the MIT release is a good common baseline.

              This  option implies --rfc1991 --disable-mdc --no-force-v4-certs --escape-from-lines --force-v3-sigs --cipher-algo
              IDEA --digest-algo MD5 --compress-algo ZIP. It also disables --textmode when encrypting.


       --pgp6 Set up all options to be as PGP 6 compliant as possible. This restricts you to the ciphers IDEA (if the IDEA plug-
              in  is  installed),  3DES,  and CAST5, the hashes MD5, SHA1 and RIPEMD160, and the compression algorithms none and
              ZIP. This also disables --throw-keyids, and making signatures with signing subkeys as PGP 6  does  not  understand
              signatures made by signing subkeys.

              This option implies --disable-mdc --escape-from-lines --force-v3-sigs.


       --pgp7 Set up all options to be as PGP 7 compliant as possible. This is identical to --pgp6 except that MDCs are not dis-
              abled, and the list of allowable ciphers is expanded to add AES128, AES192, AES256, and TWOFISH.


       --pgp8 Set up all options to be as PGP 8 compliant as possible. PGP 8 is a lot closer to the OpenPGP standard than previ-
              ous  versions  of PGP, so all this does is disable --throw-keyids and set --escape-from-lines.  All algorithms are
              allowed except for the SHA224, SHA384, and SHA512 digests.





   Doing things one usually doesn't want to do.




       -n

       --dry-run
              Don't make any changes (this is not completely implemented).


       --list-only
              Changes the behaviour of some commands. This is like --dry-run but different in some cases. The semantic  of  this
              command  may be extended in the future. Currently it only skips the actual decryption pass and therefore enables a
              fast listing of the encryption keys.


       -i

       --interactive
              Prompt before overwriting any files.


       --debug-level level
              Select the debug level for investigating problems. level may be a numeric value or by a keyword:


              none   No debugging at all.  A value of less than 1 may be used instead of the keyword.

              basic  Some basic debug messages.  A value between 1 and 2 may be used instead of the keyword.

              advanced
                     More verbose debug messages.  A value between 3 and 5 may be used instead of the keyword.

              expert Even more detailed messages.  A value between 6 and 8 may be used instead of the keyword.

              guru   All of the debug messages you can get. A value greater than 8 may be used instead of the keyword.  The cre-
                     ation of hash tracing files is only enabled if the keyword is used.

       How  these  messages are mapped to the actual debugging flags is not specified and may change with newer releases of this
       program. They are however carefully selected to best aid in debugging.


       --debug flags
              Set debugging flags. All flags are or-ed and flags may be given in C syntax (e.g. 0x0042).


       --debug-all
              Set all useful debugging flags.



       --faked-system-time epoch
              This option is only useful for testing; it sets the system time back or forth to epoch which is the number of sec-
              onds  elapsed  since  the  year  1970.   Alternatively  epoch  may  be  given  as  a  full  ISO  time string (e.g.
              "20070924T154812").


       --enable-progress-filter
              Enable certain PROGRESS status outputs. This option allows frontends to display a progress indicator while gpg  is
              processing larger files.  There is a slight performance overhead using it.


       --status-fd n
              Write special status strings to the file descriptor n.  See the file DETAILS in the documentation for a listing of
              them.


       --status-file file
              Same as --status-fd, except the status data is written to file file.


       --logger-fd n
              Write log output to file descriptor n and not to STDERR.


       --log-file file

       --logger-file file
              Same as --logger-fd, except the logger data is written to file file.  Note that --log-file is only implemented for
              GnuPG-2.


       --attribute-fd n
              Write  attribute subpackets to the file descriptor n. This is most useful for use with --status-fd, since the sta-
              tus messages are needed to separate out the various subpackets from the stream delivered to the file descriptor.


       --attribute-file file
              Same as --attribute-fd, except the attribute data is written to file file.


       --comment string

       --no-comments
              Use string as a comment string in clear text signatures and ASCII armored messages  or  keys  (see  --armor).  The
              default  behavior is not to use a comment string. --comment may be repeated multiple times to get multiple comment
              strings. --no-comments removes all comments.  It is a good idea to keep the length of a single  comment  below  60
              characters  to  avoid  problems  with  mail programs wrapping such lines.  Note that comment lines, like all other
              header lines, are not protected by the signature.


       --emit-version

       --no-emit-version
              Force inclusion of the version string in ASCII armored output.  --no-emit-version disables this option.


       --sig-notation name=value

       --cert-notation name=value

       -N, --set-notation name=value
              Put the name value pair into the signature as notation data.  name must consist only of  printable  characters  or
              spaces, and must contain a '@' character in the form keynameATdomain.com (substituting the appropriate key-
              name and domain name, of course).  This is to help prevent pollution of the IETF reserved notation namespace.  The
              --expert  flag  overrides  the  '@'  check.  value may be any printable string; it will be encoded in UTF8, so you
              should check that your --display-charset is set correctly. If you prefix name with an exclamation  mark  (!),  the
              notation  data will be flagged as critical (rfc2440:5.2.3.15). --sig-notation sets a notation for data signatures.
              --cert-notation sets a notation for key signatures (certifications). --set-notation sets both.

              There are special codes that may be used in notation names. "%k" will be expanded into the key ID of the key being
              signed, "%K" into the long key ID of the key being signed, "%f" into the fingerprint of the key being signed, "%s"
              into the key ID of the key making the signature, "%S" into the long key ID of the key making the  signature,  "%g"
              into  the  fingerprint of the key making the signature (which might be a subkey), "%p" into the fingerprint of the
              primary key of the key making the signature, "%c" into the signature count from the OpenPGP  smartcard,  and  "%%"
              results in a single "%". %k, %K, and %f are only meaningful when making a key signature (certification), and %c is
              only meaningful when using the OpenPGP smartcard.


       --sig-policy-url string

       --cert-policy-url string

       --set-policy-url string
              Use string as a Policy URL for signatures (rfc2440:5.2.3.19).  If you prefix it with an exclamation mark (!),  the
              policy URL packet will be flagged as critical. --sig-policy-url sets a policy url for data signatures. --cert-pol-
              icy-url sets a policy url for key signatures (certifications). --set-policy-url sets both.

              The same %-expandos used for notation data are available here as well.


       --sig-keyserver-url string
              Use string as a preferred keyserver URL for data signatures. If you prefix it with an exclamation  mark  (!),  the
              keyserver URL packet will be flagged as critical.

              The same %-expandos used for notation data are available here as well.


       --set-filename string
              Use  string  as  the  filename  which  is stored inside messages.  This overrides the default, which is to use the
              actual filename of the file being encrypted.


       --for-your-eyes-only

       --no-for-your-eyes-only
              Set the `for your eyes only' flag in the message. This causes GnuPG to refuse to save the file unless the --output
              option  is  given,  and PGP to use a "secure viewer" with a claimed Tempest-resistant font to display the message.
              This option overrides --set-filename.  --no-for-your-eyes-only disables this option.


       --use-embedded-filename

       --no-use-embedded-filename
              Try to create a file with a name as embedded in the data. This can be a dangerous option as it allows to overwrite
              files. Defaults to no.


       --cipher-algo name
              Use  name  as  cipher  algorithm.  Running the program with the command --version yields a list of supported algo-
              rithms. If this is not used the cipher algorithm is selected from the preferences stored with the key. In general,
              you  do  not  want to use this option as it allows you to violate the OpenPGP standard.  --personal-cipher-prefer-
              ences is the safe way to accomplish the same thing.


       --digest-algo name
              Use name as the message digest algorithm. Running the program with the command --version yields  a  list  of  sup-
              ported  algorithms.  In  general, you do not want to use this option as it allows you to violate the OpenPGP stan-
              dard. --personal-digest-preferences is the safe way to accomplish the same thing.


       --compress-algo name
              Use compression algorithm name. "zlib" is RFC-1950 ZLIB compression. "zip" is RFC-1951 ZIP  compression  which  is
              used  by  PGP.  "bzip2" is a more modern compression scheme that can compress some things better than zip or zlib,
              but at the cost of more memory used during compression and decompression. "uncompressed" or "none"  disables  com-
              pression.  If  this  option  is  not used, the default behavior is to examine the recipient key preferences to see
              which algorithms the recipient supports. If all else fails, ZIP is used for maximum compatibility.

              ZLIB may give better compression results than ZIP, as the compression window size is not limited to 8k. BZIP2  may
              give  even  better  compression results than that, but will use a significantly larger amount of memory while com-
              pressing and decompressing. This may be significant in low memory situations. Note, however, that  PGP  (all  ver-
              sions)  only  supports ZIP compression. Using any algorithm other than ZIP or "none" will make the message unread-
              able with PGP. In general, you do not want to use this option as it allows you to violate  the  OpenPGP  standard.
              --personal-compress-preferences is the safe way to accomplish the same thing.


       --cert-digest-algo name
              Use  name  as the message digest algorithm used when signing a key. Running the program with the command --version
              yields a list of supported algorithms. Be aware that if you choose an algorithm  that  GnuPG  supports  but  other
              OpenPGP implementations do not, then some users will not be able to use the key signatures you make, or quite pos-
              sibly your entire key.


       --disable-cipher-algo name
              Never allow the use of name as cipher algorithm.  The given name will not be checked so that a later loaded  algo-
              rithm will still get disabled.


       --disable-pubkey-algo name
              Never  allow  the  use of name as public key algorithm.  The given name will not be checked so that a later loaded
              algorithm will still get disabled.


       --throw-keyids

       --no-throw-keyids
              Do not put the recipient key IDs into encrypted messages. This helps to hide the receivers of the message and is a
              limited countermeasure against traffic analysis. ([Using a little social engineering anyone who is able to decrypt
              the message can check whether one of the other recipients is the one he suspects.])  On the receiving side, it may
              slow down the decryption process because all available secret keys must be tried.  --no-throw-keyids disables this
              option. This option is essentially the same as using --hidden-recipient for all recipients.


       --not-dash-escaped
              This option changes the behavior of cleartext signatures so that they can be used for patch files. You should  not
              send  such  an  armored  file  via  email because all spaces and line endings are hashed too. You can not use this
              option for data which has 5 dashes at the beginning of a line, patch files don't have this. A special armor header
              line tells GnuPG about this cleartext signature option.


       --escape-from-lines

       --no-escape-from-lines
              Because  some  mailers change lines starting with "From " to ">From " it is good to handle such lines in a special
              way when creating cleartext signatures to prevent the mail system from breaking the signature. Note that all other
              PGP versions do it this way too.  Enabled by default. --no-escape-from-lines disables this option.


       --passphrase-repeat n
              Specify  how  many  times  gpg2  will request a new passphrase be repeated.  This is useful for helping memorize a
              passphrase.  Defaults to 1 repetition.


       --passphrase-fd n
              Read the passphrase from file descriptor n. Only the first line will be read from file descriptor n. If you use  0
              for  n,  the  passphrase  will be read from STDIN. This can only be used if only one passphrase is supplied.  Note
              that this passphrase is only used if the option --batch has also been given.  This is different from gpg.


       --passphrase-file file
              Read the passphrase from file file. Only the first line will be read from file file. This can only be used if only
              one  passphrase  is  supplied. Obviously, a passphrase stored in a file is of questionable security if other users
              can read this file. Don't use this option if you can avoid it.  Note that this passphrase  is  only  used  if  the
              option --batch has also been given.  This is different from gpg.


       --passphrase string
              Use string as the passphrase. This can only be used if only one passphrase is supplied. Obviously, this is of very
              questionable security on a multi-user system. Don't use  this  option  if  you  can  avoid  it.   Note  that  this
              passphrase is only used if the option --batch has also been given.  This is different from gpg.


       --command-fd n
              This  is  a replacement for the deprecated shared-memory IPC mode.  If this option is enabled, user input on ques-
              tions is not expected from the TTY but from the given file descriptor. It should be used together  with  --status-
              fd. See the file doc/DETAILS in the source distribution for details on how to use it.


       --command-file file
              Same as --command-fd, except the commands are read out of file file


       --allow-non-selfsigned-uid

       --no-allow-non-selfsigned-uid
              Allow  the import and use of keys with user IDs which are not self-signed. This is not recommended, as a non self-
              signed user ID is trivial to forge. --no-allow-non-selfsigned-uid disables.


       --allow-freeform-uid
              Disable all checks on the form of the user ID while generating a new one. This option should only be used in  very
              special environments as it does not ensure the de-facto standard format of user IDs.


       --ignore-time-conflict
              GnuPG  normally  checks  that  the  timestamps associated with keys and signatures have plausible values. However,
              sometimes a signature seems to be older than the key due to clock problems. This option makes these checks just  a
              warning. See also --ignore-valid-from for timestamp issues on subkeys.


       --ignore-valid-from
              GnuPG normally does not select and use subkeys created in the future.  This option allows the use of such keys and
              thus exhibits the pre-1.0.7 behaviour. You should not use this option unless there is some clock problem. See also
              --ignore-time-conflict for timestamp issues with signatures.


       --ignore-crc-error
              The  ASCII  armor used by OpenPGP is protected by a CRC checksum against transmission errors. Occasionally the CRC
              gets mangled somewhere on the transmission channel but the actual content (which is protected by the OpenPGP  pro-
              tocol anyway) is still okay. This option allows GnuPG to ignore CRC errors.


       --ignore-mdc-error
              This  option  changes  a MDC integrity protection failure into a warning.  This can be useful if a message is par-
              tially corrupt, but it is necessary to get as much data as possible out of the corrupt message.  However, be aware
              that a MDC protection failure may also mean that the message was tampered with intentionally by an attacker.


       --no-default-keyring
              Do not add the default keyrings to the list of keyrings. Note that GnuPG will not operate without any keyrings, so
              if you use this option and do not provide alternate keyrings via --keyring or --secret-keyring,  then  GnuPG  will
              still use the default public or secret keyrings.


       --skip-verify
              Skip the signature verification step. This may be used to make the decryption faster if the signature verification
              is not needed.


       --with-key-data
              Print key listings delimited by colons (like --with-colons) and print the public key data.


       --fast-list-mode
              Changes the output of the list commands to work faster; this is achieved by leaving some parts empty. Some  appli-
              cations don't need the user ID and the trust information given in the listings. By using this options they can get
              a faster listing. The exact behaviour of this option may change in future  versions.   If  you  are  missing  some
              information, don't use this option.


       --no-literal
              This is not for normal use. Use the source to see for what it might be useful.


       --set-filesize
              This is not for normal use. Use the source to see for what it might be useful.


       --show-session-key
              Display the session key used for one message. See --override-session-key for the counterpart of this option.

              We  think  that  Key  Escrow  is  a Bad Thing; however the user should have the freedom to decide whether to go to
              prison or to reveal the content of one specific message without compromising all messages ever encrypted  for  one
              secret key. DON'T USE IT UNLESS YOU ARE REALLY FORCED TO DO SO.


       --override-session-key string
              Don't  use  the public key but the session key string. The format of this string is the same as the one printed by
              --show-session-key. This option is normally not used but comes handy in case someone forces you to reveal the con-
              tent of an encrypted message; using this option you can do this without handing out the secret key.


       --ask-sig-expire

       --no-ask-sig-expire
              When  making a data signature, prompt for an expiration time. If this option is not specified, the expiration time
              set via --default-sig-expire is used. --no-ask-sig-expire disables this option.


       --default-sig-expire
              The default expiration time to use for signature expiration. Valid values are "0" for no expiration, a number fol-
              lowed  by  the  letter  d  (for  days),  w (for weeks), m (for months), or y (for years) (for example "2m" for two
              months, or "5y" for five years), or an absolute date in the form YYYY-MM-DD. Defaults to "0".


       --ask-cert-expire

       --no-ask-cert-expire
              When making a key signature, prompt for an expiration time. If this option is not specified, the  expiration  time
              set via --default-cert-expire is used. --no-ask-cert-expire disables this option.


       --default-cert-expire
              The default expiration time to use for key signature expiration.  Valid values are "0" for no expiration, a number
              followed by the letter d (for days), w (for weeks), m (for months), or y (for years) (for  example  "2m"  for  two
              months, or "5y" for five years), or an absolute date in the form YYYY-MM-DD. Defaults to "0".


       --allow-secret-key-import
              This is an obsolete option and is not used anywhere.


       --allow-multiple-messages

       --no-allow-multiple-messages
              Allow  processing  of multiple OpenPGP messages contained in a single file or stream.  Some programs that call GPG
              are not prepared to deal with multiple messages being processed together, so this option  defaults  to  no.   Note
              that versions of GPG prior to 1.4.7 always allowed multiple messages.

              Warning: Do not use this option unless you need it as a temporary workaround!



       --enable-special-filenames
              This  options enables a mode in which filenames of the form `-&n', where n is a non-negative decimal number, refer
              to the file descriptor n and not to a file with that name.


       --no-expensive-trust-checks
              Experimental use only.


       --preserve-permissions
              Don't change the permissions of a secret keyring back to user read/write only. Use this option only if you  really
              know what you are doing.


       --default-preference-list string
              Set  the  list of default preferences to string. This preference list is used for new keys and becomes the default
              for "setpref" in the edit menu.


       --default-keyserver-url name
              Set the default keyserver URL to name. This keyserver will be used as the keyserver URL when writing a  new  self-
              signature on a key, which includes key generation and changing preferences.


       --list-config
              Display  various  internal  configuration  parameters of GnuPG. This option is intended for external programs that
              call GnuPG to perform tasks, and is thus not generally useful. See the file `doc/DETAILS' in the source  distribu-
              tion  for  the details of which configuration items may be listed. --list-config is only usable with --with-colons
              set.


       --gpgconf-list
              This command is similar to --list-config but in general only internally used by the gpgconf tool.


       --gpgconf-test
              This is more or less dummy action.  However it parses the configuration file and returns with failure if the  con-
              figuration  file  would  prevent gpg from startup.  Thus it may be used to run a syntax check on the configuration
              file.




   Deprecated options





       --show-photos

       --no-show-photos
              Causes --list-keys, --list-sigs, --list-public-keys, --list-secret-keys, and verifying a signature to also display
              the  photo  ID  attached  to  the  key, if any. See also --photo-viewer. These options are deprecated. Use --list-
              options [no-]show-photos and/or --verify-options [no-]show-photos instead.


       --show-keyring
              Display the keyring name at the head of key listings to show which keyring a given key resides on. This option  is
              deprecated: use --list-options [no-]show-keyring instead.



       --always-trust
              Identical to --trust-model always. This option is deprecated.


       --show-notation

       --no-show-notation
              Show  signature notations in the --list-sigs or --check-sigs listings as well as when verifying a signature with a
              notation in it. These options  are  deprecated.  Use  --list-options  [no-]show-notation  and/or  --verify-options
              [no-]show-notation instead.


       --show-policy-url

       --no-show-policy-url
              Show  policy  URLs in the --list-sigs or --check-sigs listings as well as when verifying a signature with a policy
              URL in  it.  These  options  are  deprecated.  Use  --list-options  [no-]show-policy-url  and/or  --verify-options
              [no-]show-policy-url instead.






EXAMPLES
       gpg -se -r Bob file
              sign and encrypt for user Bob


       gpg --clearsign file
              make a clear text signature


       gpg -sb file
              make a detached signature


       gpg -u 0x12345678 -sb file
              make a detached signature with the key 0x12345678


       gpg --list-keys user_ID
              show keys


       gpg --fingerprint user_ID
              show fingerprint


       gpg --verify pgpfile

       gpg --verify sigfile
              Verify  the  signature  of  the  file but do not output the data. The second form is used for detached signatures,
              where sigfile is the detached signature (either ASCII armored or binary) and are the signed data; if this  is  not
              given, the name of the file holding the signed data is constructed by cutting off the extension (".asc" or ".sig")
              of sigfile or by asking the user for the filename.




HOW TO SPECIFY A USER ID
       There are different ways to specify a user ID to GnuPG.  Some of them are only valid for gpg others  are  only  good  for
       gpgsm.  Here is the entire list of ways to specify a key:



       By key Id.
              This format is deduced from the length of the string and its content or 0x prefix. The key Id of an X.509 certifi-
              cate are the low 64 bits of its SHA-1 fingerprint.  The use of key Ids is just a shortcut, for all automated  pro-
              cessing the fingerprint should be used.

              When  using  gpg an exclamation mark (!) may be appended to force using the specified primary or secondary key and
              not to try and calculate which primary or secondary key to use.

              The last four lines of the example give the key ID in their long form as internally used by the OpenPGP  protocol.
              You can see the long key ID using the option --with-colons.

         234567C4
         0F34E556E
         01347A56A
         0xAB123456

         234AABBCC34567C4
         0F323456784E56EAB
         01AB3FED1347A5612
         0x234AABBCC34567C4




       By fingerprint.
              This  format  is  deduced  from the length of the string and its content or the 0x prefix.  Note, that only the 20
              byte version fingerprint is available with gpgsm (i.e. the SHA-1 hash of the certificate).

              When using gpg an exclamation mark (!) may be appended to force using the specified primary or secondary  key  and
              not to try and calculate which primary or secondary key to use.

              The  best way to specify a key Id is by using the fingerprint.  This avoids any ambiguities in case that there are
              duplicated key IDs.

         1234343434343434C434343434343434
         123434343434343C3434343434343734349A3434
         0E12343434343434343434EAB3484343434343434
         0xE12343434343434343434EAB3484343434343434


       (gpgsm also accepts colons between each pair of hexadecimal digits because this  is  the  de-facto  standard  on  how  to
       present X.509 fingerprints.)


       By exact match on OpenPGP user ID.
              This is denoted by a leading equal sign. It does not make sense for X.509 certificates.

         =Heinrich Heine <heinrichhATuni-duesseldorf.de>


       By exact match on an email address.
              This is indicated by enclosing the email address in the usual way with left and right angles.

         <heinrichhATuni-duesseldorf.de>



       By word match.
              All  words  must match exactly (not case sensitive) but can appear in any order in the user ID or a subjects name.
              Words are any sequences of letters, digits, the underscore and all characters with bit 7 set.

         +Heinrich Heine duesseldorf


       By exact match on the subject's DN.
              This is indicated by a leading slash, directly followed by the RFC-2253 encoded DN of the subject.  Note that  you
              can't  use  the  string  printed by "gpgsm --list-keys" because that one as been reordered and modified for better
              readability; use --with-colons to print the raw (but standard escaped) RFC-2253 string

         /CN=Heinrich Heine,O=Poets,L=Paris,C=FR


       By exact match on the issuer's DN.
              This is indicated by a leading hash mark, directly followed by a slash and then directly followed by  the  rfc2253
              encoded DN of the issuer.  This should return the Root cert of the issuer.  See note above.

         #/CN=Root Cert,O=Poets,L=Paris,C=FR



       By exact match on serial number and issuer's DN.
              This  is  indicated by a hash mark, followed by the hexadecimal representation of the serial number, then followed
              by a slash and the RFC-2253 encoded DN of the issuer. See note above.

         #4F03/CN=Root Cert,O=Poets,L=Paris,C=FR


       By keygrip
              This is indicated by an ampersand followed by the 40 hex digits of a keygrip.  gpgsm prints the keygrip when using
              the command --dump-cert.  It does not yet work for OpenPGP keys.

         &D75F22C3F86E355877348498CDC92BD21010A480



       By substring match.
              This  is  the default mode but applications may want to explicitly indicate this by putting the asterisk in front.
              Match is not case sensitive.

         Heine
         *Heine



       Please note that we have reused the hash mark identifier which was used in old GnuPG versions to indicate the  so  called
       local-id.  It is not anymore used and there should be no conflict when used with X.509 stuff.

       Using the RFC-2253 format of DNs has the drawback that it is not possible to map them back to the original encoding, how-
       ever we don't have to do this because our key database stores this encoding as meta data.





FILES
       There are a few configuration files to control certain aspects of gpg2's operation. Unless noted, they  are  expected  in
       the current home directory (see: [option --homedir]).



       gpg.conf
              This  is the standard configuration file read by gpg2 on startup.  It may contain any valid long option; the lead-
              ing two dashes may not be entered and the option may not be abbreviated.  This default name may be changed on  the
              command line (see: [option --options]).  You should backup this file.


       Note  that  on  larger installations, it is useful to put predefined files into the directory `/etc/skel/.gnupg/' so that
       newly created users start up with a working configuration.  For existing users the a small helper script is  provided  to
       create these files (see: [addgnupghome]).

       For  internal purposes gpg2 creates and maintains a few other files; They all live in in the current home directory (see:
       [option --homedir]).  Only the gpg2 may modify these files.



       ~/.gnupg/secring.gpg
              The secret keyring.  You should backup this file.


       ~/.gnupg/secring.gpg.lock
              The lock file for the secret keyring.


       ~/.gnupg/pubring.gpg
              The public keyring.  You should backup this file.


       ~/.gnupg/pubring.gpg.lock
              The lock file for the public keyring.


       ~/.gnupg/trustdb.gpg
              The trust database.  There is no need to backup this file; it is better to  backup  the  ownertrust  values  (see:
              [option --export-ownertrust]).


       ~/.gnupg/trustdb.gpg.lock
              The lock file for the trust database.


       ~/.gnupg/random_seed
              A file used to preserve the state of the internal random pool.


       /usr[/local]/share/gnupg/options.skel
              The skeleton options file.


       /usr[/local]/lib/gnupg/
              Default location for extensions.


       Operation is further controlled by a few environment variables:



       HOME   Used to locate the default home directory.


       GNUPGHOME
              If set directory used instead of "~/.gnupg".


       GPG_AGENT_INFO
              Used  to  locate the gpg-agent.  The value consists of 3 colon delimited fields: The first is the path to the Unix
              Domain Socket, the second the PID of the gpg-agent and the protocol version which should be set to 1. When  start-
              ing  the gpg-agent as described in its documentation, this variable is set to the correct value. The option --gpg-
              agent-info can be used to override it.


       PINENTRY_USER_DATA
              This value is passed via gpg-agent to pinentry.  It is useful to convey extra information to a custom pinentry.


       COLUMNS

       LINES  Used to size some displays to the full size of the screen.



       LANGUAGE
              Apart from its use by GNU, it is used in the W32 version to override the language selection done through the  Reg-
              istry.   If  used and set to a valid and available language name (langid), the file with the translation is loaded
              from gpgdir/gnupg.nls/langid.mo.  Here gpgdir is the directory out of which the gpg binary has been loaded.  If it
              can't be loaded the Registry is tried and as last resort the native Windows locale system is used.





BUGS
       On older systems this program should be installed as setuid(root). This is necessary to lock memory pages. Locking memory
       pages prevents the operating system from writing memory pages (which may contain passphrases or other sensitive material)
       to  disk.  If you get no warning message about insecure memory your operating system supports locking without being root.
       The program drops root privileges as soon as locked memory is allocated.

       Note also that some systems (especially laptops) have the ability to ``suspend to disk'' (also known as ``safe sleep'' or
       ``hibernate'').   This writes all memory to disk before going into a low power or even powered off mode.  Unless measures
       are taken in the operating system to protect the saved memory, passphrases or other sensitive material may be recoverable
       from it later.

       Before  you  report a bug you should first search the mailing list archives for similar problems and second check whether
       such a bug has already been reported to our bug tracker at http://bugs.gnupg.org .



SEE ALSO
       gpgv(1), gpgsm(1), gpg-agent(1)

       The full documentation for this tool is maintained as a Texinfo manual.  If GnuPG  and  the  info  program  are  properly
       installed at your site, the command

         info gnupg

       should give you access to the complete manual including a menu structure and an index.



GnuPG 2.0.18                                               2011-09-20                                                    GPG2(1)