ENDHOSTENT(3P)                                      POSIX Programmer's Manual                                     ENDHOSTENT(3P)



PROLOG
       This  manual  page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (con-
       sult the corresponding Linux manual page for details of Linux behavior), or the  interface  may  not  be  implemented  on
       Linux.

NAME
       endhostent, gethostent, sethostent - network host database functions

SYNOPSIS
       #include <netdb.h>

       void endhostent(void);
       struct hostent *gethostent(void);
       void sethostent(int stayopen);


DESCRIPTION
       These  functions  shall  retrieve information about hosts. This information is considered to be stored in a database that
       can be accessed sequentially or randomly. The implementation of this database is unspecified.

       Note:  In many cases this database is implemented by the Domain Name System, as documented  in  RFC 1034,  RFC 1035,  and
              RFC 1886.


       The sethostent() function shall open a connection to the database and set the next entry for retrieval to the first entry
       in the database. If the stayopen argument is non-zero, the connection shall not be closed  by  a  call  to  gethostent(),
       gethostbyname(), or gethostbyaddr(), and the implementation may maintain an open file descriptor.

       The  gethostent() function shall read the next entry in the database, opening and closing a connection to the database as
       necessary.

       Entries shall be returned in hostent structures. Refer to gethostbyaddr() for a definition of the hostent structure.

       The endhostent() function shall close the connection to the database, releasing any open file descriptor.

       These functions need not be reentrant. A function that is not required to be reentrant is not required to be thread-safe.

RETURN VALUE
       Upon successful completion, the gethostent() function shall return a pointer to a  hostent  structure  if  the  requested
       entry was found, and a null pointer if the end of the database was reached or the requested entry was not found.

ERRORS
       No errors are defined for endhostent(), gethostent(), and sethostent().

       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       The  gethostent()  function  may  return  pointers to static data, which may be overwritten by subsequent calls to any of
       these functions.

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       endservent(), gethostbyaddr(), the Base Definitions volume of IEEE Std 1003.1-2001, <netdb.h>

COPYRIGHT
       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003  Edition,  Standard  for
       Information  Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copy-
       right (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any
       discrepancy  between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group
       Standard  is  the  referee   document.   The   original   Standard   can   be   obtained   online   at   http://www.open-
       group.org/unix/online.html .



IEEE/The Open Group                                           2003                                                ENDHOSTENT(3P)