This manual page is part of the POSIX Programmer's Manual. The Linux
implementation of this interface may differ (consult the corresponding Linux
manual page for details of Linux behavior), or the interface may not be
implemented on Linux.
sched_getscheduler — get scheduling policy (REALTIME)
int sched_getscheduler(pid_t pid);
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 process.
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.
The sched_getscheduler() function shall fail if:
- The requesting process does not have permission to determine the
scheduling policy of the specified process.
- No process can be found corresponding to that specified by
The following sections are informative.
The Base Definitions volume of POSIX.1‐2017,
Portions of this text are reprinted and reproduced in electronic form from IEEE
Std 1003.1-2017, Standard for Information Technology -- Portable Operating
System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018
Edition, Copyright (C) 2018 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 .
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