DESCRIPTION
 The  sched_setscheduler system call sets the scheduling policy and scheduling parameters of the process specified by  pid to  policy and the parameters specified in the 
.Vt sched_param structure pointed to by  param, respectively. The value of the  sched_priority member in the  param structure must be any integer within the inclusive priority range for the scheduling policy specified by  policy.  In this implementation, if the value of  pid is negative the system call will fail. 
 If a process specified by  pid exists and if the calling process has permission, the scheduling policy and scheduling parameters will be set for the process whose process ID is equal to  pid. 
 If  pid is zero, the scheduling policy and scheduling parameters are set for the calling process. 
 In this implementation, the policy of when a process can affect the scheduling parameters of another process is specified in  -p1003.1b-93 as a write-style operation. 
 The scheduling policies are in  <sched.h>: