The ALTPRI privilege allows the user's process to:
- Increase its own base priority
- Set the base priority of a target process
- Change the priority of its batch or print jobs
The base priority is increased by executing the Set Priority ($SETPRI) system service or the DCL command SET PROCESS/PRIORITY. As a rule, this system service lets a process set its own base priority or the base priority of another process. However, one process can set the priority of a second process only if one of the following conditions applies:
- The process calling the $SETPRI system service has the same UIC as the target process.
- The calling process has process control privilege (GROUP or WORLD) over the target process.
With ALTPRI, a process can create a detached process with a priority higher than its own. It creates such a process by using an optional argument to the Create Process ($CREPRC) system service or to the DCL command RUN/PRIORITY. ALTPRI also lets you adjust the scheduling priority of a job ($SNDJBC) to a value even greater than that established with the system parameter MAXQUEPRI. Do not grant this privilege widely; if unqualified users have the unrestricted ability to set base priorities, fair and orderly scheduling of processes for execution can easily be disrupted.