POSIX_SPAWNATTR_DESTROY(3P)                         POSIX Programmer's Manual                        POSIX_SPAWNATTR_DESTROY(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
       posix_spawnattr_destroy, posix_spawnattr_init - destroy and initialize spawn attributes object (ADVANCED REALTIME)

SYNOPSIS
       #include <spawn.h>

       int posix_spawnattr_destroy(posix_spawnattr_t *attr);
       int posix_spawnattr_init(posix_spawnattr_t *attr);


DESCRIPTION
       The posix_spawnattr_destroy() function shall destroy a spawn attributes object. A destroyed attr attributes object can be
       reinitialized using posix_spawnattr_init(); the results of otherwise referencing the object after it has  been  destroyed
       are  undefined.  An implementation may cause posix_spawnattr_destroy() to set the object referenced by attr to an invalid
       value.

       The posix_spawnattr_init() function shall initialize a spawn attributes object attr with the default value for all of the
       individual attributes used by the implementation. Results are undefined if posix_spawnattr_init() is called specifying an
       already initialized attr attributes object.

       A spawn attributes object is of type posix_spawnattr_t (defined in <spawn.h>) and is used to specify the  inheritance  of
       process  attributes across a spawn operation. IEEE Std 1003.1-2001 does not define comparison or assignment operators for
       the type posix_spawnattr_t.

       Each implementation shall document the individual attributes it uses and their default values  unless  these  values  are
       defined  by  IEEE Std 1003.1-2001. Attributes not defined by IEEE Std 1003.1-2001, their default values, and the names of
       the associated functions to get and set those attribute values are implementation-defined.

       The resulting spawn attributes object (possibly modified by setting individual attribute values), is used to  modify  the
       behavior  of  posix_spawn() or posix_spawnp(). After a spawn attributes object has been used to spawn a process by a call
       to a posix_spawn() or posix_spawnp(), any function affecting the attributes  object  (including  destruction)  shall  not
       affect any process that has been spawned in this way.

RETURN VALUE
       Upon  successful  completion, posix_spawnattr_destroy() and posix_spawnattr_init() shall return zero; otherwise, an error
       number shall be returned to indicate the error.

ERRORS
       The posix_spawnattr_init() function shall fail if:

       ENOMEM Insufficient memory exists to initialize the spawn attributes object.


       The posix_spawnattr_destroy() function may fail if:

       EINVAL The value specified by attr is invalid.


       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       These functions are part of the Spawn option and need not be provided on all implementations.

RATIONALE
       The original spawn interface proposed in IEEE Std 1003.1-2001 defined the attributes  that  specify  the  inheritance  of
       process  attributes  across  a  spawn  operation  as  a  structure.  In  order to be able to separate optional individual
       attributes under their appropriate options (that is, the spawn-schedparam and spawn-schedpolicy attributes depending upon
       the  Process  Scheduling  option),  and  also  for  extensibility  and  consistency  with the newer POSIX interfaces, the
       attributes interface has been changed to an opaque data type. This interface now consists of the type  posix_spawnattr_t,
       representing  a  spawn  attributes  object,  together  with  associated functions to initialize or destroy the attributes
       object, and to set or get each individual attribute. Although the new object-oriented interface is more verbose than  the
       original structure, it is simple to use, more extensible, and easy to implement.

FUTURE DIRECTIONS
       None.

SEE ALSO
       posix_spawn(),   posix_spawnattr_getsigdefault(),  posix_spawnattr_getflags(),  posix_spawnattr_getpgroup(),  posix_spaw-
       nattr_getschedparam(), posix_spawnattr_getschedpolicy(),  posix_spawnattr_getsigmask(),  posix_spawnattr_setsigdefault(),
       posix_spawnattr_setflags(),  posix_spawnattr_setpgroup(), posix_spawnattr_setsigmask(), posix_spawnattr_setschedpolicy(),
       posix_spawnattr_setschedparam(), posix_spawnp(), the Base Definitions volume of IEEE Std 1003.1-2001, <spawn.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                                   POSIX_SPAWNATTR_DESTROY(3P)