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 (consult the correspond-
ing 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. POSIX.1-2008 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
POSIX.1-2008. Attributes not defined by POSIX.1-2008, 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 POSIX.1-2008 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 consis-
tency 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 struc-
ture, 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_spawnattr_getschedparam(),
posix_spawnattr_getschedpolicy(), posix_spawnattr_getsigmask()
The Base Definitions volume of POSIX.1-2008, <spawn.h>
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2013 Edition, Standard for Information Technol-
ogy -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, Copyright (C) 2013 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) 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 Stan-
dard is the referee document. The original Standard can be obtained online at http://www.unix.org/online.html .
Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source
files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .
IEEE
/The Open Group 2013 POSIX_SPAWNATTR_DESTROY(3P)