xref: /freebsd/share/man/man3/pthread_schedparam.3 (revision c98323078dede7579020518ec84cdcb478e5c142)
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28.\" $FreeBSD$
29.Dd May 1, 2000
30.Dt PTHREAD_SCHEDPARAM 3
31.Os
32.Sh NAME
33.Nm pthread_setschedparam ,
34.Nm pthread_getschedparam
35.Nd thread scheduling parameter manipulation
36.Sh LIBRARY
37.Lb libc_r
38.Lb libpthread
39.Lb libthr
40.Sh SYNOPSIS
41.In pthread.h
42.Ft int
43.Fn pthread_setschedparam "pthread_t thread" "int policy" "const struct sched_param *param"
44.Ft int
45.Fn pthread_getschedparam "pthread_t thread" "int *policy" "struct sched_param *param"
46.Sh DESCRIPTION
47The
48.Fn pthread_setschedparam
49and
50.Fn pthread_getschedparam
51functions set and get the scheduling parameters of individual threads.
52The scheduling policy for a thread can either be
53.Dv SCHED_FIFO
54(first in, first out) or
55.Dv SCHED_RR
56(round-robin).
57The thread priority (accessed via
58.Va param->sched_priority )
59must be at least
60.Dv PTHREAD_MIN_PRIORITY
61and no more than
62.Dv PTHREAD_MAX_PRIORITY .
63.Sh RETURN VALUES
64If successful, these functions return 0.
65Otherwise, an error number is returned to indicate the error.
66.Sh ERRORS
67The
68.Fn pthread_setschedparam
69function will fail if:
70.Bl -tag -width Er
71.It Bq Er EINVAL
72Invalid value for
73.Va policy .
74.It Bq Er ENOTSUP
75Invalid value for scheduling parameters.
76.It Bq Er ESRCH
77Non-existent thread
78.Va thread .
79.El
80.Pp
81The
82.Fn pthread_getschedparam
83function will fail if:
84.Bl -tag -width Er
85.It Bq Er ESRCH
86Non-existent thread
87.Va thread .
88.El
89.Sh STANDARDS
90The
91.Fn pthread_setschedparam
92and
93.Fn pthread_getschedparam
94functions conform to
95.St -susv2
96