Name

pthread_setprio − Changes the current priority of a thread

Syntax

#include <pthread.h>

int pthread_setprio (thread, priority)
pthread_t thread;
int priority;

Arguments

thread Thread whose priority is changed. 

priority New priority value of the thread specified in thread. The priority value is dependent upon scheduling policy.  Valid values fall within one of the following three ranges. 

If you create a new thread without specifying a threads attributes object that contains a changed priority attribute, the default priority of the newly created thread is the midpoint between PRI_OTHER_MIN and PRI_OTHER_MAX (the midpoint between the minimum and the maximum for the SCHED_OTHER policy). 

Description

This routine changes the current priority of a thread.  A thread can change its own priority using the identifier returned by pthread_self. 

Changing the priority of a thread can cause it to start executing or be preempted by another thread. The effect of setting different priority values depends on the scheduling priority assigned to the thread.  The initial scheduling priority is set by calling the pthread_attr_setprio routine. 

Note that pthread_attr_setprio sets the priority attribute that is used to establish the priority of a new thread when it is created.  However, pthread_setprio changes the priority of an existing thread. 

Return Values

If an error condition occurs, this routine returns -1 and sets errno to the corresponding error value.  Possible return values are as follows.