общие атрибуты переменной условия (shared condition variable attributes)
Пролог (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.
Имя (Name)
pthread_condattr_getpshared, pthread_condattr_setpshared — get
and set the process-shared condition variable attributes
Синопсис (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);
Описание (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. See Section 2.9.9,
Synchronization Object Copies and Alternative Mappings for
further requirements. The default value of the attribute is
PTHREAD_PROCESS_PRIVATE.
The behavior is undefined if the value specified by the attr
argument to pthread_condattr_getpshared() or
pthread_condattr_setpshared() does not refer to an initialized
condition variable attributes object.
Возвращаемое значение (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.
Ошибки (Error)
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.
Примеры (Examples)
None.
Использование в приложениях (Application usage)
None.
Обоснование (Rationale)
If an implementation detects that the value specified by the attr
argument to pthread_condattr_getpshared() or
pthread_condattr_setpshared() does not refer to an initialized
condition variable attributes object, it is recommended that the
function should fail and report an [EINVAL] error.
Будущие направления (Future directions)
None.
Смотри также (See also)
pthread_create(3p), pthread_cond_destroy(3p),
pthread_condattr_destroy(3p), pthread_mutex_destroy(3p)
The Base Definitions volume of POSIX.1‐2017, pthread.h(0p)
