Fill characters for input message fields

MFS uses fill characters to pad message fields when the length of the data received from the device is less than the specified field length, no data for the field is received and no default literal is defined, or the data received from SLU P contains nulls and NULL=DELETE is specified.

The fill characters that can be selected are a blank (X'40'), any EBCDIC hexadecimal character (X'hh'), or an EBCDIC graphic character (C'c'). Null compression, which causes compression of the message to the left by the amount of missing data, can also be selected. How MFS actually pads the message fields is a function of the selected fill character and the message formatting option being used.