NAME
pthread_condattr_getpshared, pthread_condattr_setpshared - get and set
the process-shared condition variable attributes
SYNOPSIS
#include <pthread.h>
int pthread_condattr_getpshared(const pthread_condattr_t *restrict
attr,
int *restrict pshared);
int pthread_condattr_setpshared(pthread_condattr_t *attr,
int pshared);
DESCRIPTION
The pthread_condattr_getpshared() function shall obtain the value of
the process-shared attribute from the attributes object referenced by
attr. The pthread_condattr_setpshared() function shall set the process-
shared attribute in an initialized attributes object referenced by
attr.
The process-shared attribute is set to PTHREAD_PROCESS_SHARED to permit
a condition variable to be operated upon by any thread that has access
to the memory where the condition variable is allocated, even if the
condition variable is allocated in memory that is shared by multiple
processes. If the process-shared attribute is PTHREAD_PROCESS_PRIVATE,
the condition variable shall only be operated upon by threads created
within the same process as the thread that initialized the condition
variable; if threads of differing processes attempt to operate on such
a condition variable, the behavior is undefined. The default value of
the attribute is PTHREAD_PROCESS_PRIVATE.
RETURN VALUE
If successful, the pthread_condattr_setpshared() function shall return
zero; otherwise, an error number shall be returned to indicate the
error.
If successful, the pthread_condattr_getpshared() function shall return
zero and store the value of the process-shared attribute of attr into
the object referenced by the pshared parameter. Otherwise, an error
number shall be returned to indicate the error.
ERRORS
The pthread_condattr_getpshared() and pthread_condattr_setpshared()
functions may fail if:
EINVAL The value specified by attr is invalid.
The pthread_condattr_setpshared() function may fail if:
EINVAL The new value specified for the attribute is outside the range
of legal values for that attribute.
These functions shall not return an error code of [EINTR].
The following sections are informative.
EXAMPLES
None.
APPLICATION USAGE
None.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
pthread_create() , pthread_cond_destroy() , pthread_condattr_destroy()
, pthread_mutex_destroy() , the Base Definitions volume of
IEEE Std 1003.1-2001, <pthread.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, Copyright (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.opengroup.org/unix/online.html .