PTHREAD_CONDATTR_GETPSHARED(3C)PTHREAD_CONDATTR_GETPSHARED(3C)NAME
pthread_condattr_getpshared, pthread_condattr_setpshared - get or set
process-shared condition variable attributes
SYNOPSIS
cc -mt [ flag... ] file... -lpthread [ library... ]
#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 obtains the value of the
process-shared attribute from the attributes object referenced by attr.
The pthread_condattr_setpshared() function is used to set the process-
shared attribute in an initialized attributes object referenced by
attr.
The process-shared attribute is set to PTHREAD_PROCESS_SHARED to per‐
mit 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 multi‐
ple processes. If the process-shared attribute is PTHREAD_PROCESS_PRI‐
VATE, the condition variable will only be operated upon by threads cre‐
ated within the same process as the thread that initialized the condi‐
tion 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.
Additional attributes, their default values, and the names of the asso‐
ciated functions to get and set those attribute values are implementa‐
tion-dependent.
RETURN VALUES
If successful, the pthread_condattr_setpshared() function returns 0.
Otherwise, an error number is returned to indicate the error.
If successful, the pthread_condattr_getpshared() function returns 0 and
stores the value of the process-shared attribute of attr into the
object referenced by the pshared parameter. Otherwise, an error number
is 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 will fail if:
EINVAL
The new value specified for the attribute is outside the
range of legal values for that attribute.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌────────────────────┬─────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├────────────────────┼─────────────────┤
│Interface Stability │ Standard │
├────────────────────┼─────────────────┤
│MT-Level │ MT-Safe │
└────────────────────┴─────────────────┘
SEE ALSOpthread_condattr_init(3C), pthread_create(3C), pthread_mutex_init(3C),
pthread_cond_init(3C), attributes(5), standards(5)
Mar 23, 2005 PTHREAD_CONDATTR_GETPSHARED(3C)
