# pthread_attr_setinheritsched

## NAME



           pthread_attr_setinheritsched, pthread_attr_getinheritsched -
           set/get inherit-scheduler attribute in thread attributes object
    


## LIBRARY



           POSIX threads library (_libpthread_ , _-lpthread_)
    


## SYNOPSIS



           **#include <pthread.h>**
    
           **int pthread_attr_setinheritsched(pthread_attr_t ***_attr_**,**
                                            **int** _inheritsched_**);**
           **int pthread_attr_getinheritsched(const pthread_attr_t *restrict** _attr_**,**
                                            **int *restrict** _inheritsched_**);**
    


## DESCRIPTION



           The **pthread_attr_setinheritsched**() function sets the inherit-
           scheduler attribute of the thread attributes object referred to by
           _attr_ to the value specified in _inheritsched_.  The inherit-
           scheduler attribute determines whether a thread created using the
           thread attributes object _attr_ will inherit its scheduling
           attributes from the calling thread or whether it will take them
           from _attr_.
    
           The following scheduling attributes are affected by the inherit-
           scheduler attribute: scheduling policy
           (pthread_attr_setschedpolicy(3)), scheduling priority
           (pthread_attr_setschedparam(3)), and contention scope
           (pthread_attr_setscope(3)).
    
           The following values may be specified in _inheritsched_ :
    
           **PTHREAD_INHERIT_SCHED**
                  Threads that are created using _attr_ inherit scheduling
                  attributes from the creating thread; the scheduling
                  attributes in _attr_ are ignored.
    
           **PTHREAD_EXPLICIT_SCHED**
                  Threads that are created using _attr_ take their scheduling
                  attributes from the values specified by the attributes
                  object.
    
           The default setting of the inherit-scheduler attribute in a newly
           initialized thread attributes object is **PTHREAD_INHERIT_SCHED**.
    
           The **pthread_attr_getinheritsched**() returns the inherit-scheduler
           attribute of the thread attributes object _attr_ in the buffer
           pointed to by _inheritsched_.
    


## RETURN VALUE



           On success, these functions return 0; on error, they return a
           nonzero error number.
    


## ERRORS



           **pthread_attr_setinheritsched**() can fail with the following error:
    
           **EINVAL** Invalid value in _inheritsched_.
    
           POSIX.1 also documents an optional **ENOTSUP** error ("attempt was
           made to set the attribute to an unsupported value") for
           **pthread_attr_setinheritsched**().
    


## ATTRIBUTES



           For an explanation of the terms used in this section, see
           attributes(7).
           ┌──────────────────────────────────────┬───────────────┬─────────┐
           │ **Interface** │ **Attribute** │ **Value** │
           ├──────────────────────────────────────┼───────────────┼─────────┤
           │ **pthread_attr_setinheritsched**(),      │ Thread safety │ MT-Safe │
           │ **pthread_attr_getinheritsched**()       │               │         │
           └──────────────────────────────────────┴───────────────┴─────────┘
    


## STANDARDS



           POSIX.1-2008.
    


## BUGS



           As at glibc 2.8, if a thread attributes object is initialized
           using pthread_attr_init(3), then the scheduling policy of the
           attributes object is set to **SCHED_OTHER** and the scheduling
           priority is set to 0.  However, if the inherit-scheduler attribute
           is then set to **PTHREAD_EXPLICIT_SCHED** , then a thread created using
           the attribute object wrongly inherits its scheduling attributes
           from the creating thread.  This bug does not occur if either the
           scheduling policy or scheduling priority attribute is explicitly
           set in the thread attributes object before calling
           pthread_create(3).
    


## EXAMPLES



           See pthread_setschedparam(3).
    


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