A console session must be active before your program invokes GETMSG. The settings in your console profile must indicate that system messages (solicited and/or unsolicited) are not to be displayed at the terminal. You can use the CONSPROF command to change the settings in the console profile.

To ensure that the proper message is delivered to your application program, use the command and response token (CART), and its mask. The CART is a token that lets you associate MVS™ system commands and subcommands with their responses. The mask is a search argument that GETMSG uses with the CART parameter for obtaining a message. The CART and mask parameters are valid only if you are retrieving solicited messages.

You cannot selectively retrieve unsolicited messages. Unsolicited messages are not associated with CARTs and are shared by applications.