PTHREAD_CONDATTR_INIT(3C) Standard C Library Functions

NAME

pthread_condattr_init, pthread_condattr_destroy - initialize or
destroy condition variable attributes object

SYNOPSIS

cc -mt [ flag... ] file... -lpthread [ library... ]
#include <pthread.h>

int pthread_condattr_init(pthread_condattr_t *attr);


int pthread_condattr_destroy(pthread_condattr_t *attr);

DESCRIPTION

The pthread_condattr_init() function initializes a condition variable
attributes object attr with the default value for all of the
attributes defined by the implementation.


At present, the only attribute available is the scope of condition
variables. The default scope of the attribute is
PTHREAD_PROCESS_PRIVATE.


Attempts to initialize previously initialized condition variable
attributes object will leave the storage allocated by the previous
initialization unallocated.


After a condition variable attributes object has been used to
initialize one or more condition variables, any function affecting
the attributes object (including destruction) does not affect any
previously initialized condition variables.


The pthread_condattr_destroy() function destroys a condition variable
attributes object; the object becomes, in effect, uninitialized. An
implementation may cause pthread_condattr_destroy() to set the object
referenced by attr to an invalid value. A destroyed condition
variable attributes object can be re-initialized using
pthread_condattr_init(); the results of otherwise referencing the
object after it has been destroyed are undefined.


Additional attributes, their default values, and the names of the
associated functions to get and set those attribute values are
implementation-dependent.

RETURN VALUES

If successful, the pthread_condattr_init() and
pthread_condattr_destroy() functions return 0. Otherwise, an error
number is returned to indicate the error.

ERRORS

The pthread_condattr_init() function will fail if:

ENOMEM
Insufficient memory exists to initialize the condition
variable attributes object.


The pthread_condattr_destroy() function may fail if:

EINVAL
The value specified by attr is invalid.

ATTRIBUTES

See attributes(7) for descriptions of the following attributes:


+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | Standard |
+--------------------+-----------------+
|MT-Level | MT-Safe |
+--------------------+-----------------+

SEE ALSO

pthread_cond_init(3C), pthread_condattr_getpshared(3C),
pthread_condattr_setpshared(3C), pthread_create(3C),
pthread_mutex_init(3C), attributes(7), standards(7)

March 23, 2005 PTHREAD_CONDATTR_INIT(3C)