pthread_condattr_init.txt

来自「Pthread lib库完整说明文档」· 文本 代码 · 共 89 行

pthread_condattr_init Subroutine



Purpose

Creates a condition attributes object and initializes it with default
values.

Library

Threads Library (libpthreads.a)

Syntax

#include <pthread.h>

int pthread_condattr_init (attr)
pthread_condattr_t *attr;

Description

The pthread_condattr_init subroutine creates a new condition attributes
object attr. The new condition attributes object is initialized with
the following default values:


------------------------------------------------------------------------------------------------------------------
|Initialized if _POSIX_THREAD_PROCESS_SHARED is defined          
                                               |
|------------------------------------------------------------|---------------------------------------------------|
|Attribute                                                   |Default
value                                      |
|------------------------------------------------------------|---------------------------------------------------|
|Pshared                                                     |PTHREAD_PROCESS_PRIVATE
                           |
|                                                            |the
default ensures compatibility with             |
|                                                            |implementations
that do not support this POSIX     |
|                                                            |option.
                                           |
------------------------------------------------------------------------------------------------------------------


Note:	The pthread.h header file must be the first included file of
each source file using the threads library.

Parameter

attr	Specifes the condition attributes object to be created.

Return Values

Upon successful completion, the new condition attributes object is
filled with default values and returned via the attr parameter, and
0 is returned. Otherwise, an error code is returned.

Error Code

The pthread_condattr_init subroutine is unsuccessful if the following
is true:

EINVAL	The attr parameter is not valid.

ENOMEM	There is not sufficient memory to create the condition attributes
object.

Implementation Specifics

This subroutine is part of the Base Operating System (BOS) Runtime.

The process sharing POSIX option is not implemented in AIX.

Related Information

The pthread_condattr_setpshared subroutine, pthread_cond_init subroutine,
pthread_condattr_destroy subroutine.

Using Condition Variables.

Threads Library Options.

Threads Library Quick Reference.