posix_spawnattr_destroy.3p (5316B)
- '\" et
- .TH POSIX_SPAWNATTR_DESTROY "3P" 2017 "IEEE/The Open Group" "POSIX Programmer's Manual"
- .\"
- .SH PROLOG
- This manual page is part of the POSIX Programmer's Manual.
- The Linux implementation of this interface may differ (consult
- the corresponding Linux manual page for details of Linux behavior),
- or the interface may not be implemented on Linux.
- .\"
- .SH NAME
- posix_spawnattr_destroy,
- posix_spawnattr_init
- \(em destroy and initialize spawn attributes object
- (\fBADVANCED REALTIME\fP)
- .SH SYNOPSIS
- .LP
- .nf
- #include <spawn.h>
- .P
- int posix_spawnattr_destroy(posix_spawnattr_t *\fIattr\fP);
- int posix_spawnattr_init(posix_spawnattr_t *\fIattr\fP);
- .fi
- .SH DESCRIPTION
- The
- \fIposix_spawnattr_destroy\fR()
- function shall destroy a spawn attributes object. A destroyed
- .IR attr
- attributes object can be reinitialized using
- \fIposix_spawnattr_init\fR();
- the results of otherwise referencing the object after it
- has been destroyed are undefined. An implementation may cause
- \fIposix_spawnattr_destroy\fR()
- to set the object referenced by
- .IR attr
- to an invalid value.
- .P
- The
- \fIposix_spawnattr_init\fR()
- function shall initialize a spawn attributes object
- .IR attr
- with the default value for all of the individual attributes used by the
- implementation. Results are undefined if
- \fIposix_spawnattr_init\fR()
- is called specifying an already initialized
- .IR attr
- attributes object.
- .P
- A spawn attributes object is of type
- .BR posix_spawnattr_t
- (defined in
- .IR <spawn.h> )
- and is used to specify the inheritance of process attributes across a
- spawn operation. POSIX.1\(hy2008 does not define comparison or assignment
- operators for the type
- .BR posix_spawnattr_t .
- .P
- Each implementation shall document the individual attributes it uses
- and their default values unless these values are defined by POSIX.1\(hy2008.
- Attributes not defined by POSIX.1\(hy2008, their default values, and the names of
- the associated functions to get and set those attribute values are
- implementation-defined.
- .P
- The resulting spawn attributes object (possibly modified by setting
- individual attribute values), is used to modify the behavior of
- \fIposix_spawn\fR()
- or
- \fIposix_spawnp\fR().
- After a spawn attributes object has been used to spawn a process by a
- call to a
- \fIposix_spawn\fR()
- or
- \fIposix_spawnp\fR(),
- any function affecting the attributes object (including destruction)
- shall not affect any process that has been spawned in this way.
- .SH "RETURN VALUE"
- Upon successful completion,
- \fIposix_spawnattr_destroy\fR()
- and
- \fIposix_spawnattr_init\fR()
- shall return zero; otherwise, an error number shall be returned to
- indicate the error.
- .SH ERRORS
- The
- \fIposix_spawnattr_init\fR()
- function shall fail if:
- .TP
- .BR ENOMEM
- Insufficient memory exists to initialize the spawn attributes object.
- .P
- The
- \fIposix_spawnattr_destroy\fR()
- function may fail if:
- .TP
- .BR EINVAL
- The value specified by attr is invalid.
- .LP
- .IR "The following sections are informative."
- .SH EXAMPLES
- None.
- .SH "APPLICATION USAGE"
- These functions are part of the Spawn option and need not be
- provided on all implementations.
- .SH RATIONALE
- The original spawn interface proposed in POSIX.1\(hy2008 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
- .IR spawn-schedparam
- and
- .IR 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
- .BR 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.
- .SH "FUTURE DIRECTIONS"
- None.
- .SH "SEE ALSO"
- .ad l
- .IR "\fIposix_spawn\fR\^(\|)",
- .IR "\fIposix_spawnattr_getsigdefault\fR\^(\|)",
- .IR "\fIposix_spawnattr_getflags\fR\^(\|)",
- .IR "\fIposix_spawnattr_getpgroup\fR\^(\|)",
- .IR "\fIposix_spawnattr_getschedparam\fR\^(\|)",
- .IR "\fIposix_spawnattr_getschedpolicy\fR\^(\|)",
- .IR "\fIposix_spawnattr_getsigmask\fR\^(\|)"
- .ad b
- .P
- The Base Definitions volume of POSIX.1\(hy2017,
- .IR "\fB<spawn.h>\fP"
- .\"
- .SH COPYRIGHT
- Portions of this text are reprinted and reproduced in electronic form
- from IEEE Std 1003.1-2017, Standard for Information Technology
- -- Portable Operating System Interface (POSIX), The Open Group Base
- Specifications Issue 7, 2018 Edition,
- Copyright (C) 2018 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.opengroup.org/unix/online.html .
- .PP
- 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 .