The sched_getscheduler() function shall return the scheduling policy of
the process specified by pid. If the value of pid is negative,
the behavior of the sched_getscheduler() function is unspecified.
The values that can be returned by sched_getscheduler() are defined in
the <sched.h> header.
If a process specified by pid exists, and if the calling process has
permission, the scheduling policy shall be returned for the process whose
process ID is equal to pid.
If pid is zero, the scheduling policy shall be returned for the calling
Upon successful completion, the sched_getscheduler() function shall
return the scheduling policy of the specified process. If unsuccessful, the
function shall return -1 and set errno to indicate the error.
Portions of this text are reprinted and reproduced in electronic form from IEEE
Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable
Operating System Interface (POSIX), The Open Group Base Specifications Issue
6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics
Engineers, Inc and The Open Group. In the event of any discrepancy between
this version and the original IEEE and The Open Group Standard, the original
IEEE and The Open Group Standard is the referee document. The original
Standard can be obtained online at http://www.opengroup.org/unix/online.html