NAME

rtprio − execute process with realtime priority

SYNOPSIS

rtprio priority command [ arguments ]
rtprio priority −pid
rtprio -t command [ arguments ]
rtprio -t −pid

DESCRIPTION

Rtprio executes command with a realtime priority, or changes the realtime priority of currently executing process pid.  Realtime priorities range from zero (highest) to 127 (lowest).  Realtime processes are not subject to priority degradation and are all of greater (scheduling) importance than non−realtime processes.  See rtprio(2) for more details. 

If -t is specified instead of a realtime priority, rtprio executes command with a timeshare (non-realtime) priority, or changes the currently executing process pid from a possibly realtime priority to a timeshare priority.  The former is useful to spawn a timeshare priority command from a realtime priority shell. 

If −t is not specified, command is not scheduled, or pid’s realtime priority is not changed, if the user is not a member of a group having PRIV_RTPRIO access and is not the super−user.  When changing the realtime priority of a currently executing process, the effective user ID of the calling process must be super-user, or the real or effective user ID must match the real or saved user ID of the process to be modified. 

RETURN VALUE

Rtprio returns exit status 0 if command is successfully scheduled or if pid’s realtime priority is successfully changed, 1 if command is not executable or pid does not exist, and 2 if command (pid) lacks realtime capability, or the invoker’s effective user ID is not super-user, or the real or effective user ID does not match the real or saved user ID of the process being changed. 

EXAMPLES

The following example executes the a.out file at a real-time priority of 100:

rtprio 100 a.out

The following example sets the currently running process with pid 24217 to a real-time priority of 40:

rtprio 40 -24217

AUTHOR

Rtprio was developed by HP. 

SEE ALSO

setprivgrp(1M), getprivgrp(2), rtprio(2). 

Hewlett-Packard Company  —  May 11, 2021