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'\" et
.TH PTHREAD_CONDATTR_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
pthread_condattr_destroy,
pthread_condattr_init
\(em destroy and initialize the condition variable attributes object
.SH SYNOPSIS
.LP
.nf
#include <pthread.h>
.P
int pthread_condattr_destroy(pthread_condattr_t *\fIattr\fP);
int pthread_condattr_init(pthread_condattr_t *\fIattr\fP);
.fi
.SH DESCRIPTION
The
\fIpthread_condattr_destroy\fR()
function shall destroy a condition variable attributes object; the
object becomes, in effect, uninitialized. An implementation may cause
\fIpthread_condattr_destroy\fR()
to set the object referenced by
.IR attr
to an invalid value. A destroyed
.IR attr
attributes object can be reinitialized using
\fIpthread_condattr_init\fR();
the results of otherwise referencing the object after it
has been destroyed are undefined.
.P
The
\fIpthread_condattr_init\fR()
function shall initialize a condition variable attributes object
.IR attr
with the default value for all of the attributes defined by the
implementation.
.P
Results are undefined if
\fIpthread_condattr_init\fR()
is called specifying an already initialized
.IR attr
attributes object.
.P
After a condition variable attributes object has been used to
initialize one or more condition variables, any function affecting the
attributes object (including destruction) shall not affect any
previously initialized condition variables.
.P
This volume of POSIX.1\(hy2017 requires two attributes, the
.IR clock
attribute and the
.IR process-shared
attribute.
.P
Additional attributes, their default values, and the names of the
associated functions to get and set those attribute values are
implementation-defined.
.P
The behavior is undefined if the value specified by the
.IR attr
argument to
\fIpthread_condattr_destroy\fR()
does not refer to an initialized condition variable attributes object.
.SH "RETURN VALUE"
If successful, the
\fIpthread_condattr_destroy\fR()
and
\fIpthread_condattr_init\fR()
functions shall return zero; otherwise, an error number shall be
returned to indicate the error.
.SH ERRORS
The
\fIpthread_condattr_init\fR()
function shall fail if:
.TP
.BR ENOMEM
Insufficient memory exists to initialize the condition variable
attributes object.
.P
These functions shall not return an error code of
.BR [EINTR] .
.LP
.IR "The following sections are informative."
.SH EXAMPLES
None.
.SH "APPLICATION USAGE"
None.
.SH RATIONALE
A
.IR process-shared
attribute has been defined for condition variables for the same reason
it has been defined for mutexes.
.P
If an implementation detects that the value specified by the
.IR attr
argument to
\fIpthread_condattr_destroy\fR()
does not refer to an initialized condition variable attributes object,
it is recommended that the function should fail and report an
.BR [EINVAL]
error.
.P
See also
.IR "\fIpthread_attr_destroy\fR\^(\|)"
and
.IR "\fIpthread_mutex_destroy\fR\^(\|)".
.SH "FUTURE DIRECTIONS"
None.
.SH "SEE ALSO"
.ad l
.IR "\fIpthread_attr_destroy\fR\^(\|)",
.IR "\fIpthread_cond_destroy\fR\^(\|)",
.IR "\fIpthread_condattr_getpshared\fR\^(\|)",
.IR "\fIpthread_create\fR\^(\|)",
.IR "\fIpthread_mutex_destroy\fR\^(\|)"
.ad b
.P
The Base Definitions volume of POSIX.1\(hy2017,
.IR "\fB<pthread.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 .
|
