DragonFly On-Line Manual Pages
SCHED_GET_PRIORITY_MA... DragonFly System Calls ManualSCHED_GET_PRIORITY_MA...
NAME
sched_get_priority_max, sched_get_priority_min, sched_rr_get_interval --
get scheduling parameter limits
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <sched.h>
int
sched_get_priority_max(int policy);
int
sched_get_priority_min(int policy);
int
sched_rr_get_interval(pid_t pid, struct timespec *interval);
DESCRIPTION
The sched_get_priority_max() and sched_get_priority_min() functions
return the appropriate maximum or minimum, respectively, for the schedul-
ing policy specified by policy. The sched_rr_get_interval() function
updates the timespec structure referenced by the interval argument to
contain the current execution time limit (i.e., time quantum) for the
process specified by pid. If pid is zero, the current execution time
limit for the calling process is returned.
The value of policy should be one of the scheduling policy values defined
in <sched.h>:
SCHED_FIFO First-in-first-out fixed priority scheduling with no round
robin scheduling;
SCHED_OTHER The standard time sharing scheduler;
SCHED_RR Round-robin scheduling across same priority processes.
RETURN VALUES
If successful, the sched_get_priority_max() and sched_get_priority_min()
functions shall return the appropriate maximum or minimum values, respec-
tively. If unsuccessful, they shall return a value of -1 and set errno
to indicate the error.
The sched_rr_get_interval() function returns the value 0 if successful;
otherwise the value -1 is returned and the global variable errno is set
to indicate the error.
ERRORS
On failure errno will be set to the corresponding value:
[EINVAL] The value of the policy parameter does not represent a
defined scheduling policy.
[ENOSYS] The sched_get_priority_max(),
sched_get_priority_min(), and sched_rr_get_interval()
functions are not supported by the implementation.
[ESRCH] No process can be found corresponding to that speci-
fied by pid.
SEE ALSO
sched_getparam(2), sched_getscheduler(2), sched_setparam(2),
sched_setscheduler(2)
STANDARDS
The sched_setscheduler() and sched_getscheduler() functions conform to
IEEE Std 1003.1b-1993 (``POSIX.1'').
DragonFly 3.5 March 12, 1998 DragonFly 3.5