Certain parameters in IEASYSxx (such as CLOCK, CON, and MLPA) allow you to specify the list option (L). If you specify the L option, and message suppression is not active, the system writes all of the statements read from the associated parmlib member to the operator's console during system initialization. If message suppression is active (the default), the system writes the list to the console log only. While the L option is generally allowed, unless otherwise documented, you should not expect that any action is taken as a result of specifying it.
To ensure that messages are not suppressed, specify an appropriate initialization message suppression indicator (IMSI character) on the LOAD parameter. The IMSI characters that do not suppress messages are A, C, D, M, and T.
For more information about the LOAD parameter, see the topic on loading the system software in z/OS MVS System Commands.