MSG statement

The MSG statement initiates and names a message input or output definition.

Format for MSG TYPE=INPUT or OUTPUT

Read syntax diagramSkip visual syntax diagramlabelMSGTYPE=INPUTOUTPUT,SOR=( formatname,IGNORE),OPT=123,NXT= msgcontrolblockname

Format for MSG TYPE=OUTPUT only

Read syntax diagramSkip visual syntax diagram,PAGE=NOYES,FILL=C' 'C' c'NULLPT

Parameters

label
A one- to eight-character alphanumeric name must be specified. This label can be referred to in the NXT operand of another message descriptor.
TYPE=
Defines this definition as a message INPUT or OUTPUT control block. The default is INPUT.
SOR=
Specifies the source name of the FMT statement which, with the DEV statement, defines the terminal or remote program data fields processed by this message descriptor. Specifying IGNORE for TYPE=OUTPUT causes MFS to use data fields specified for the device whose FEAT= operand specifies IGNORE in the device format definition. For TYPE=INPUT, IGNORE should be specified only if the corresponding message output descriptor specified IGNORE. If you use SOR=IGNORE, you must specify IGNORE on both the message input descriptor and the message output descriptor.
OPT=
Specifies the message formatting option used by MFS to edit messages. The default is 1.
NXT=
Specifies the name of a message descriptor to be used to map the next expected message as a result of processing a message using this message descriptor. If TYPE=INPUT, NXT= specifies a message output descriptor. If TYPE=OUTPUT, NXT= specifies a message input descriptor. For ISC output, NXT= becomes the RDPN in the ATTACH FM header.

If TYPE=OUTPUT and the formatname specified in the SOR= operand contains formats for 3270 or 3270P device types, the msgcontrolblockname referred to by NXT= must use the same formatname.

PAGE=
Specifies whether (YES) or not (NO) operator logical paging (forward and backward paging) is to be provided for messages edited using this control block. This operand is valid only if TYPE=OUTPUT. The default is NO, which means that only forward paging of physical pages is provided.
FILL=
Specifies a fill character for output device fields. This operand is valid only if TYPE=OUTPUT. The default is C' '. The fill specification is ignored unless FILL=NONE is specified on the DPAGE statement in the FMT definition. For 3270 output when EGCS fields are present, only FILL=PT or FILL=NULL should be specified. A FILL=PT erases an output field (either a 1- or 2-byte field) only when data is sent to the field, and thus does not erase the DFLD if the application program message omits the MFLD. For DPM-Bn, if OFTAB is specified, FILL= is ignored and FILL=NULL is assumed.
C' '
Character ' ' is the default used to fill device fields. The blank character is interpreted as is X'40' which is a valid printable character.
C'c'
Character 'c' is used to fill device fields. For 3270 display devices, any specification with a value less than X'3F' is changed to X'00' for control characters or to X'40' for other nongraphic characters. For all other devices, any FILL=C'c' specification with a value less than X'3F' is ignored and defaulted to X'3F' (which is equivalent to a specification of FILL=NULL).

If you specify C'c' as X'36', it changes to either X'0' or X'40' as X'36' is not a valid printable character.

NULL
Specifies that fields are not to be filled. For devices other than 3270 and SLU 2 display, 'compacted lines' are produced when message data does not fill device fields.
PT
Is identical to NULL except for 3270 and SLU 2 display. For 3270 and SLU 2 display, PT specifies that output fields that do not fill the device field (DFLD) are followed by a program tab character to erase data previously in the field.