| 1 | .TH GETPRIORITY 2 "Jul 1, 2005"
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| 2 | .UC 4
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| 3 | .SH NAME
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| 4 | getpriority, setpriority \- get and set scheduling priority
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| 5 | .SH SYNOPSIS
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| 6 | .nf
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| 7 | .ft B
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| 8 | #include <sys/resource.h>
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| 9 |
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| 10 | int getpriority(int \fIwhich\fP, int \fIwho\fP)
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| 11 | int setpriority(int \fIwhich\fP, int \fIwho\fP, int \fIprio\fP)
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| 12 | .SH DESCRIPTION
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| 13 | .B Getpriority
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| 14 | returns the scheduling priority of the process, process group, or user
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| 15 | referred to in \fIwho\fP. Which of the three is indicated in
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| 16 | \fIwhich\fP, by PRIO_PROCESS, PRIO_PGRP and PRIO_USER, respectively.
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| 17 | In MINIX 3, currently only PRIO_PROCESS is implemented.
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| 18 |
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| 19 | The range of the returned value is between PRIO_MIN and PRIO_MAX,
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| 20 | currently between -20 and 20, and is the so-called nice value of
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| 21 | a process. The higher the nice value, the less favourable the scheduling
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| 22 | priority.
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| 23 |
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| 24 | .B Setpriority
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| 25 | sets the priority indicated by \fIwho\fP and \fIwhich\fP to \fIprio\fP.
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| 26 | \fIprio\fP, which is the nice value, may only be lowered by the super-user.
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| 27 | .SH RETURN VALUES
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| 28 | These functions both return -1 on failure, and set errno in this case.
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| 29 | Because
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| 30 | .B getpriority
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| 31 | can return -1 as the real nice value, the caller has to reset errno
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| 32 | and check errno afterwards to distinguish between an error condition
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| 33 | and a negative nice value.
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| 34 | .SH SEE ALSO
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| 35 | nice(1)
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| 36 | .SH AUTHOR
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| 37 | Ben Gras <beng@few.vu.nl>
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