freebsd-skq/lib/libc/sys/sched_get_priority_max.2
dufault 8ed0defc6e Finish _POSIX_PRIORITY_SCHEDULING. Needs P1003_1B and
_KPOSIX_PRIORITY_SCHEDULING options to work.  Changes:

Change all "posix4" to "p1003_1b".  Misnamed files are left
as "posix4" until I'm told if I can simply delete them and add
new ones;

Add _POSIX_PRIORITY_SCHEDULING system calls for FreeBSD and Linux;

Add man pages for _POSIX_PRIORITY_SCHEDULING system calls;

Add options to LINT;

Minor fixes to P1003_1B code during testing.
1998-03-28 11:51:01 +00:00

122 lines
3.6 KiB
Groff

.\" $Id:$
.\" Copyright (c) 1998 HD Associates, Inc.
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.Dd Mar 12, 1998
.Dt SCHED_GET_PRIORITY_MAX 2
.Os BSD 4
.Sh NAME
.Nm sched_get_priority_max ,
.Nm sched_get_priority_min ,
.Nm sched_rr_get_interval
.Nd Get scheduling parameter limits
.Sh SYNOPSIS
.Fd #include <sched.h>
.Ft int
.Fn sched_get_priority_max "int policy"
.Ft int
.Fn sched_get_priority_min "int policy"
.Ft int
.Fn sched_rr_get_interval "pid_t pid" "struct timespec *interval"
.Sh DESCRIPTION
The
.Fn sched_get_priority_max
and
.Fn sched_get_priority_min
functions return the appropriate maximum or minimum, respectfully,
for the scheduling policy specified by policy. The
.Fn sched_rr_get_interval
function updates the
.Fa timespec
structure referenced by the
.Fa interval
argument to contain the current execution time limit (i.e., time
quantum) for the process specified by
.Fa pid .
If
.Fa pid
is zero, the current execution time limit for the calling process is
returned.
.Pp
The value of
.Fa policy
should be one of the scheduling policy values defined in
.Fa <sched.h> :
.Bl -tag -width [SCHED_OTHER]
.It Bq Er SCHED_FIFO
First-in-first-out fixed priority scheduling with no round robin scheduling;
.It Bq Er SCHED_OTHER
The standard time sharing scheduler;
.It Bq Er SCHED_RR
Round-robin scheduling across same priority processes.
.El
.Sh RETURN
If successful, the
.Fn sched_get_priority_max
and
.Fn sched_get_priority_min
functions shall return the appropriate maximum or minimum values,
respectively. If unsuccessful, the shall return a value of -1 and set
.Fa errno
to indicate the error.
.Pp
If successful, the
.Fn sched_rr_get_interval
function will return 0. Otherwise, it will
return a value of -1 and set
.Fa errno
to indicate the error.
.Sh ERRORS
On failure
.Va errno
will be set to the corresponding value:
.Bl -tag -width [EFAULT]
.It Bq Er EINVAL
The value of the
.Fa policy
parameter does not represent a defined scheduling policy.
.It Bq Er ENOSYS
The
.Fn sched_get_priority_max ,
.Fn sched_get_priority_min ,
and
.Fn sched_rr_get_interval
functions are not supported by the implementation.
.It Bq Er ESRCH
No process can be found corresponding to that specified by
.Fa pid .
.El
.Sh SEE ALSO
.Xr sched_getparam 2 ,
.Xr sched_setparam 2 ,
.Xr sched_get_scheduler 2 ,
.Xr sched_set_scheduler 2
.Sh STANDARDS
The
.Fn sched_setscheduler
and
.Fn sched_getscheduler
functions conform to
.St -p1003.1b-93 .