xref: /freebsd/share/man/man3/pthread_schedparam.3 (revision f0a75d274af375d15b97b830966b99a02b7db911)
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30.Dd October 16, 2006
31.Dt PTHREAD_SCHEDPARAM 3
32.Os
33.Sh NAME
34.Nm pthread_setschedparam ,
35.Nm pthread_getschedparam
36.Nd thread scheduling parameter manipulation
37.Sh LIBRARY
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),
55.Dv SCHED_RR
56(round-robin), or
57.Dv SCHED_OTHER
58(timesharing).
59Valid thread priorities (accessed via
60.Va param->sched_priority )
61must be within the range returned by the
62.Xr sched_get_priority_min 2
63and
64.Xr sched_get_priority_max 2
65system calls.
66.Sh RETURN VALUES
67If successful, these functions return 0.
68Otherwise, an error number is returned to indicate the error.
69.Sh ERRORS
70The
71.Fn pthread_setschedparam
72function will fail if:
73.Bl -tag -width Er
74.It Bq Er EINVAL
75Invalid value for
76.Fa policy .
77.It Bq Er ENOTSUP
78Invalid value for scheduling parameters.
79.It Bq Er ESRCH
80Non-existent thread
81.Fa thread .
82.El
83.Pp
84The
85.Fn pthread_getschedparam
86function will fail if:
87.Bl -tag -width Er
88.It Bq Er ESRCH
89Non-existent thread
90.Fa thread .
91.El
92.Sh SEE ALSO
93.Xr sched_get_priority_max 2 ,
94.Xr sched_get_priority_min 2
95.Sh STANDARDS
96The
97.Fn pthread_setschedparam
98and
99.Fn pthread_getschedparam
100functions conform to
101.St -susv2 .
102