pthread_condattr_getpshared() — Get the process-shared condition variable attribute
Standards
Standards / Extensions | C or C++ | Dependencies |
---|---|---|
Language Environment Extension |
both | z/OS® V1R2 |
Format
#define _OPEN_THREADS
#define _OPEN_SYS_MUTEX_EXT
#include <pthread.h>
int pthread_condattr_getpshared(const pthread_condattr_t *attr,
int *pshared);
SUSV3:
#define _UNIX03_THREADS
#include <pthread.h>
int pthread_condattr_getpshared(const pthread_condattr_t * __restrict__attr,
int * __restrict__pshared);
General description
Gets the attribute pshared for the condition variable attribute object attr. By using attr, you can determine its process-shared value for a condition variable.
Valid values for the attribute pshared are:
- Value
- Description
- PTHREAD_PROCESS_SHARED
- Permits 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.
- PTHREAD_PROCESS_PRIVATE
- A condition variable can 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, only the process to initialize the condition
variable will succeed. When a new process is created by the parent
process it will receive a different copy of the private condition
variable which can only be used to serialize between threads in the
child process. Note: This is the default value of pshared
Returned value
If successful, 0 is returned.
If unsuccessful, -1 is returned and the errno value is set. The following
is the value of errno:
- Value
- Description
- EINVAL
- The value specified for attr is not valid.
Special behavior for Single UNIX Specification, Version 3: If unsuccessful, pthread_condattr_getpshared() returns an error number to indicate the error.
Related information
- pthread.h
- pthread_condattr_setpshared() — Set the process-shared condition variable attribute
- pthread_mutexattr_getpshared() — Get the process-shared mutex attribute
- pthread_mutexattr_setpshared() — Set the process-shared mutex attribute
- pthread_rwlockattr_getpshared() — Get the processed-shared read or write lock attribute
- pthread_rwlockattr_setpshared() — Set the process-shared read or write lock attribute