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pthread_attr_init - Initializes a thread attributes object
pthread_attr_t *attr );
DECthreads POSIX 1003.1c Library (libpthread.so)
Interfaces documented on this reference page conform to industry standards
IEEE Std 1003.1c-1995, POSIX System Application Program Interface
Address of a thread attributes object to be initialized.
This routine initializes the thread attributes object specified by the attr
argument with a set of default attribute values. A thread attributes object
is used to specify the attributes of one or more threads when they are
created. The attributes object created by this routine is used only in
calls to the pthread_create(3) routine.
The following routines change individual attributes of an initialized
thread attributes object:
The attributes of the thread attributes object are initialized to default
values. The default value of each attribute is discussed in the reference
description for each routine listed above.
When a thread attributes object is used to create a thread, the object's
attribute values determine the characteristics of the new thread. Thus,
attributes objects act as additional arguments to thread creation. Changing
the attributes of a thread attributes object does not affect any threads
that were previously created using that attributes object.
You can use the same thread attributes object in successive calls to
pthread_create(3), from any thread. (However, you cannot use the same value
of the stack address attribute to create multiple threads that might run
concurrently; threads cannot share a stack.) If more than one thread might
change the attributes in a shared attributes object, your program must use
a mutex to protect the integrity of the attributes object's contents.
When you set the scheduling policy or scheduling parameters, or both, in a
thread attributes object, you must disable scheduling inheritance if you
want the scheduling attributes you set to be used at thread creation. To
disable scheduling inheritance, before creating the new thread use the
pthread_attr_setinheritsched routine to specify the value
PTHREAD_EXPLICIT_SCHED for the inherit argument.
If an error condition occurs, the thread attributes object cannot be used,
and this routine returns an integer value indicating the type of error.
Possible return values are as follows:
0 Successful completion.
The value specified by attr is not a valid thread attributes object.
Insufficient memory exists to initialize the thread attributes object.
Functions: pthread_attr_destroy(3), pthread_attr_setdetachstate(3),
Manuals: Guide to DECthreads and Programmer's Guide
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