Originální popis anglicky:
sched_setparam, sched_getparam - set and get scheduling parameters
Návod, kniha: Linux Programmer's Manual
#include <sched.h>
int sched_setparam(pid_t pid, const struct sched_param
*p );
int sched_getparam(pid_t pid, struct sched_param
*p);
struct sched_param {
...
int sched_priority;
...
};
sched_setparam sets the scheduling parameters associated with the
scheduling policy for the process identified by
pid. If
pid is
zero, then the parameters of the current process are set. The interpretation
of the parameter
p depends on the selected policy. Currently, the
following three scheduling policies are supported under Linux:
SCHED_FIFO,
SCHED_RR, and
SCHED_OTHER.
sched_getparam retrieves the scheduling parameters for the process
identified by
pid. If
pid is zero, then the parameters of the
current process are retrieved.
sched_setparam checks the validity of
p for the scheduling policy
of the process. The parameter
p->sched_priority must lie within the
range given by
sched_get_priority_min and
sched_get_priority_max.
POSIX systems on which
sched_setparam and
sched_getparam are
available define
_POSIX_PRIORITY_SCHEDULING in <unistd.h>.
On success,
sched_setparam and
sched_getparam return 0. On error,
-1 is returned,
errno is set appropriately.
- EINVAL
- The parameter p does not make sense for the current
scheduling policy.
- EPERM
- The calling process does not have appropriate privileges. A
process calling sched_setparam needs an effective user ID equal to
the user ID or effective user ID of the process identified by pid,
or (Linux) it must have the CAP_SYS_NICE capability.
- ESRCH
- The process whose ID is pid could not be found.
POSIX.1b (formerly POSIX.4)
getpriority(2),
nice(2),
sched_get_priority_max(2),
sched_get_priority_min(2),
sched_getaffinity(2),
sched_getscheduler(2),
sched_setaffinity(2),
sched_setscheduler(2),
setpriority(2),
capabilities(7)
sched_setscheduler(2) has a description of the Linux scheduling scheme.
Programming for the real world - POSIX.4 by Bill O. Gallmeister, O'Reilly
& Associates, Inc., ISBN 1-56592-074-0
IEEE Std 1003.1b-1993 (POSIX.1b standard)
ISO/IEC 9945-1:1996
