sched.h(0P) POSIX Programmer's Manual sched.h(0P)PROLOG
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.
NAMEsched.h — execution scheduling
SYNOPSIS
#include <sched.h>
DESCRIPTION
The <sched.h> header shall define the pid_t type as described in
<sys/types.h>.
The <sched.h> header shall define the time_t type as described in
<sys/types.h>.
The <sched.h> header shall define the timespec structure as described
in <time.h>.
The <sched.h> header shall define the sched_param structure, which
shall include the scheduling parameters required for implementation of
each supported scheduling policy. This structure shall include at least
the following member:
int sched_priority Process or thread execution scheduling priority.
The sched_param structure defined in <sched.h> shall include the fol‐
lowing members in addition to those specified above:
int sched_ss_low_priority Low scheduling priority for
sporadic server.
struct timespec sched_ss_repl_period Replenishment period for
sporadic server.
struct timespec sched_ss_init_budget Initial budget for sporadic server.
int sched_ss_max_repl Maximum pending replenishments for
sporadic server.
Each process or thread is controlled by an associated scheduling policy
and priority. Associated with each policy is a priority range. Each
policy definition specifies the minimum priority range for that policy.
The priority ranges for each policy may overlap the priority ranges of
other policies.
Four scheduling policies are defined; others may be defined by the
implementation. The four standard policies are indicated by the values
of the following symbolic constants:
SCHED_FIFO First in-first out (FIFO) scheduling policy.
SCHED_RR Round robin scheduling policy.
SCHED_SPORADIC
Sporadic server scheduling policy.
SCHED_OTHER Another scheduling policy.
The values of these constants are distinct.
The following shall be declared as functions and may also be defined as
macros. Function prototypes shall be provided.
int sched_get_priority_max(int);
int sched_get_priority_min(int);
int sched_getparam(pid_t, struct sched_param *);
int sched_getscheduler(pid_t);
int sched_rr_get_interval(pid_t, struct timespec *);
int sched_setparam(pid_t, const struct sched_param *);
int sched_setscheduler(pid_t, int, const struct sched_param *);
int sched_yield(void);
Inclusion of the <sched.h> header may make visible all symbols from the
<time.h> header.
The following sections are informative.
APPLICATION USAGE
None.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
<sys_types.h>, <time.h>
The System Interfaces volume of POSIX.1‐2008, sched_get_priority_max(),
sched_getparam(), sched_getscheduler(), sched_rr_get_interval(),
sched_setparam(), sched_setscheduler(), sched_yield()COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri‐
cal and Electronics Engineers, Inc and The Open Group. (This is
POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) 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.unix.org/online.html .
Any typographical or formatting errors that appear in this page are
most likely to have been introduced during the conversion of the source
files to man page format. To report such errors, see https://www.ker‐
nel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group 2013 sched.h(0P)
