xref: /freebsd/share/man/man3/pthread_schedparam.3 (revision 38f0b757fd84d17d0fc24739a7cda160c4516d81)
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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.Sh SYNOPSIS
40.In pthread.h
41.Ft int
42.Fn pthread_setschedparam "pthread_t thread" "int policy" "const struct sched_param *param"
43.Ft int
44.Fn pthread_getschedparam "pthread_t thread" "int *policy" "struct sched_param *param"
45.Sh DESCRIPTION
46The
47.Fn pthread_setschedparam
48and
49.Fn pthread_getschedparam
50functions set and get the scheduling parameters of individual threads.
51The scheduling policy for a thread can either be
52.Dv SCHED_FIFO
53(first in, first out),
54.Dv SCHED_RR
55(round-robin), or
56.Dv SCHED_OTHER
57(timesharing).
58Valid thread priorities (accessed via
59.Va param->sched_priority )
60must be within the range returned by the
61.Xr sched_get_priority_min 2
62and
63.Xr sched_get_priority_max 2
64system calls.
65.Sh RETURN VALUES
66If successful, these functions return 0.
67Otherwise, an error number is returned to indicate the error.
68.Sh ERRORS
69The
70.Fn pthread_setschedparam
71function will fail if:
72.Bl -tag -width Er
73.It Bq Er EINVAL
74Invalid value for
75.Fa policy .
76.It Bq Er ENOTSUP
77Invalid value for scheduling parameters.
78.It Bq Er ESRCH
79Non-existent thread
80.Fa thread .
81.El
82.Pp
83The
84.Fn pthread_getschedparam
85function will fail if:
86.Bl -tag -width Er
87.It Bq Er ESRCH
88Non-existent thread
89.Fa thread .
90.El
91.Sh SEE ALSO
92.Xr sched_get_priority_max 2 ,
93.Xr sched_get_priority_min 2
94.Sh STANDARDS
95The
96.Fn pthread_setschedparam
97and
98.Fn pthread_getschedparam
99functions conform to
100.St -susv2 .
101