Using command prefix strings
Each instance of WebSphere MQ that you install must have its own command prefix string (CPF). You use the CPF to identify the z/OS subsystem that commands are intended for. It also identifies the z/OS subsystem from which messages sent to the console originate.
We can issue all MQSC commands from an authorized console by inserting the CPF before the command. If you enter commands through the system command input queue (for example, using CSQUTIL), or use the WebSphere MQ operations and control panels, you do not use the CPF.
To start a subsystem called CSQ1 whose CPF is '
+CSQ1', issue the command
+CSQ1 START QMGR from the operator console (the space between the CPF and the command is optional).
The CPF also identifies the subsystem that is returning operator messages. The following example shows
+CSQ1 as the CPF between the message number and the message text.