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32 .\" @(#)getpriority.2 8.1 (Berkeley) 6/4/93
33 .\" $FreeBSD: src/lib/libc/sys/getpriority.2,v 1.4.2.5 2001/12/14 18:34:00 ru Exp $
34 .\" $DragonFly: src/lib/libc/sys/getpriority.2,v 1.3 2008/05/01 23:36:43 swildner Exp $
42 .Nd get/set program scheduling priority
49 .Fn getpriority "int which" "int who"
51 .Fn setpriority "int which" "int who" "int prio"
54 priority of the process, process group, or user, as indicated by
71 is interpreted relative to
73 (a process identifier for
82 denotes the current process, process group, or user.
84 is a value in the range -20 to 20. The default priority is 0;
85 lower priorities cause more favorable scheduling.
89 call returns the highest priority (lowest numerical value)
90 enjoyed by any of the specified processes. The
92 call sets the priorities of all of the specified processes
93 to the specified value. Only the super-user may lower priorities.
97 can legitimately return the value -1, it is necessary
98 to clear the external variable
101 call, then check it afterward to determine
102 if a -1 is an error or a legitimate value.
112 No process was located using the
126 In addition to the errors indicated above,
131 A process was located, but neither its effective nor real user
132 ID matched the effective user ID of the caller.
134 A non super-user attempted to lower a process priority.
143 function call appeared in