The Open Group Base Specifications Issue 6
IEEE Std 1003.1, 2004 Edition
Copyright © 2001-2004 The IEEE and The Open Group, All Rights reserved.
A newer edition of this document exists here


pthread_attr_getinheritsched, pthread_attr_setinheritsched - get and set the inheritsched attribute (REALTIME THREADS)


[THR TPS] [Option Start] #include <pthread.h>

int pthread_attr_getinheritsched(const pthread_attr_t *restrict
       int *restrict
int pthread_attr_setinheritsched(pthread_attr_t *
inheritsched); [Option End]


The pthread_attr_getinheritsched(), and pthread_attr_setinheritsched() functions, respectively, shall get and set the inheritsched attribute in the attr argument.

When the attributes objects are used by pthread_create(), the inheritsched attribute determines how the other scheduling attributes of the created thread shall be set.

The supported values of inheritsched shall be:

Specifies that the thread scheduling attributes shall be inherited from the creating thread, and the scheduling attributes in this attr argument shall be ignored.
Specifies that the thread scheduling attributes shall be set to the corresponding values from this attributes object.

The symbols PTHREAD_INHERIT_SCHED and PTHREAD_EXPLICIT_SCHED are defined in the <pthread.h> header.

The following thread scheduling attributes defined by IEEE Std 1003.1-2001 are affected by the inheritsched attribute: scheduling policy ( schedpolicy), scheduling parameters ( schedparam), and scheduling contention scope ( contentionscope).


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


The pthread_attr_getinheritsched() function may fail if:

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

The pthread_attr_setinheritsched() function may fail if:

The value of inheritsched is not valid.
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].

The following sections are informative.




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

See Thread Scheduling for further details on thread scheduling attributes and their default settings.






pthread_attr_destroy(), pthread_attr_getscope(), pthread_attr_getschedpolicy(), pthread_attr_getschedparam(), pthread_create(), the Base Definitions volume of IEEE Std 1003.1-2001, <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.

Issue 6

The pthread_attr_getinheritsched() and pthread_attr_setinheritsched() 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 restrict keyword is added to the pthread_attr_getinheritsched() prototype for alignment with the ISO/IEC 9899:1999 standard.

IEEE Std 1003.1-2001/Cor 2-2004, item XSH/TC2/D6/75 is applied, clarifying the values of inheritsched in the DESCRIPTION and adding two optional [EINVAL] errors to the ERRORS section for checking when attr refers to an uninitialized thread attribute object.

IEEE Std 1003.1-2001/Cor 2-2004, item XSH/TC2/D6/77 is applied, adding a reference to Thread Scheduling in the APPLICATION USAGE section.

End of informative text.

UNIX ® is a registered Trademark of The Open Group.
POSIX ® is a registered Trademark of The IEEE.
[ Main Index | XBD | XCU | XSH | XRAT ]