Logical message consisting of one segment only

Logical message consisting of multiple segments

Header segment

Item		Position	Length (bytes)	Contents
Header	Input/output logical terminal name	0	9	Logical terminal name (including final null character) to be passed in MCF functions. Specify the same name for each segment of a multiple-segment message.
	Map name	9	9	Map name (including final null character). Specify the same name for each segment of a multiple-segment message. This specification is valid only for functions that return a map name.
	Reserved	18	9	Null character
	Segment type	27	1	One of the following characters: F First segment M Middle segment L Last segment O Single segment H Header segment
	Message length	28	4	Message length (0-2147483647)
Data	Message	32	n	The data in the segment, of the specified message length

• The following shows how the items in an MCF receive message file are related to message receive requests from a UAP via an MCF function.
  

  

• By concatenating header segments, data created in another file can be combined with the first or single segment and passed together to the UAP. The following shows how a header segment is related to a message receive request from a UAP by an MCF function.
  

  

• The following shows the relationships between the segment type specified in the segment header for a service request to an MHP and the file type at execution.

Logical message consisting of one segment only

When segment type F, M, or L is specified, the message is handled in the same way as when O is specified and no error occurs.

Segment type	File type
F	Handled as an MCF receive message file.
M
L
O
H, #	Handled as an invalid file specification. The system makes a file name inquiry.

Legend:

#: Specification other than F, M, L, O, or H.

Logical message consisting of multiple segments

When segment type L, H, or O is specified, the MHP regards the message as completed and ignores any subsequent segments. Segment type F is handled in the same way as segment type M.

Segment type			Segments received by MHP
First segment	Middle segment	Last segment
F	M	L	F, M, L
F	L	M	F, L#1
F	O	L	F, L#2
M	M	L	M, M, L
L	M	F	L#3
O	O	O	O#3
F	L	M	F, L#1
F	M	H	No segments received.#4
X	M	L
F	X	L
F	M	X
H	F	L	H#3
H	O	O	H#3

Legend:

X: Specification other than F, M, or L.

#1: M is ignored.

#2: L is ignored.

#3: The middle and subsequent segments are ignored.

#4: Handled as an invalid file specification. The system makes a file name inquiry.

Files concatenated by header segment

Files can only be concatenated when H is specified as the segment type. Otherwise, the file specifications are ignored.

Segment type (combinations for concatenation)	File type
H + (file beginning with F)	Handled as a concatenated MCF receive message file.
H + (file beginning with M)
H + (file beginning with L)
H + (file beginning with O)
H + (file beginning with #)
F, M, L, or O + (file beginning with any segment type)	The file following + is ignored.
# + (file beginning with any segment type)	Handled as an invalid file specification. The system makes a file name inquiry.

Legend:

#: Specification other than F, M, L, O, or H.

Do not use a plus sign (+), space, or tab code in the file name. Also, do not use ps or end as the file name.