PTHREAD_ATTR_GETSCOPE(3) Library Functions Manual PTHREAD_ATTR_GETSCOPE(3)

pthread_attr_getscope pthread_attr_setscope — get and set the contentionscope attribute (REALTIME THREADS)


#include <pthread.h>

int pthread_attr_getscope(const pthread_attr_t *restrict attr,
       int *restrict contentionscope);
int pthread_attr_setscope(pthread_attr_t *attr, int contentionscope);

The pthread_attr_getscope () and pthread_attr_setscope () functions, respectively, shall get and set the contentionscope attribute in the attr object.

The contentionscope attribute may have the values PTHREAD_SCOPE_SYSTEM, signifying system scheduling contention scope, or PTHREAD_SCOPE_PROCESS, signifying process scheduling contention scope. The symbols PTHREAD_SCOPE_SYSTEM and PTHREAD_SCOPE_PROCESS are defined in the <pthread.h> header.

If successful, the pthread_attr_getscope () and pthread_attr_setscope () functions shall return zero; otherwise, an error number shall be returned to indicate the error.

The pthread_attr_getscope () function may fail if:

The value specified by attr does not refer to an initialized thread attribute object.

The pthread_attr_setscope () function may fail if:

The value of contentionscope is not valid, or the value specified by attr does not refer to an initialized thread attribute object.
An attempt was made to set the attribute to an unsupported value.

These functions shall not return an error code of [EINTR].

None.

After these attributes have been set, a thread can be created with the specified attributes using pthread_create(3). Using these routines does not affect the current running thread.

See xsh_chap02_09(3) for further details on thread scheduling attributes and their default settings.

None.

None.

pthread_attr_destroy(3), pthread_attr_getinheritsched(3), pthread_attr_getschedpolicy(3), pthread_attr_getschedparam(3), pthread_create(3), the Base Definitions volume of IEEE Std 1003.1-2001 (“POSIX.1”), <pthread.h>, <sched.h>

First released in Issue 5. Included for alignment with the POSIX Threads Extension.

Marked as part of the Realtime Threads Feature Group.

The pthread_attr_getscope () and pthread_attr_setscope () functions are marked as part of the Threads and Thread Execution Scheduling options.

The [ENOSYS] error condition has been removed as stubs need not be provided if an implementation does not support the Thread Execution Scheduling option.

The keyword is added to the pthread_attr_getscope () prototype for alignment with the ISO/IEC 9899:1999 (“ISO C99”) standard.

IEEE Std 1003.1-2001 (“POSIX.1”)/Cor 2-2004, item XSH/TC2/D6/81 is applied, adding a reference to xsh_chap02_09(3) in the APPLICATION USAGE section.

IEEE Std 1003.1-2001 (“POSIX.1”)/Cor 2-2004, item XSH/TC2/D6/82 is applied, updating the ERRORS section to include optional errors for the case when attr refers to an uninitialized thread attribute object.

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January 1, 2004 posix.fail