sched.h(0P)               POSIX Programmer's Manual              sched.h(0P)

PROLOG         top

       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.

NAME         top

       sched.h — execution scheduling

SYNOPSIS         top

       #include <sched.h>

DESCRIPTION         top

       The <sched.h> header shall define the pid_t type as described in

       The <sched.h> header shall define the time_t type as described in

       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
       following 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.

                     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.



RATIONALE         top




SEE ALSO         top

       sys_types.h(0p), time.h(0p)

       The System Interfaces volume of POSIX.1‐2008,
       sched_get_priority_max(3p), sched_getparam(3p),
       sched_getscheduler(3p), sched_rr_get_interval(3p),
       sched_setparam(3p), sched_setscheduler(3p), sched_yield(3p)

COPYRIGHT         top

       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 Electrical 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 .

       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 .

IEEE/The Open Group                 2013                         sched.h(0P)