Casio Cassiopeia PA-2400 - Manual (Page 48)

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4.5.2 List File Comparison
With this function the following comparison will be made:
Comparison between the file information transferred (copied) from the partner station (parent
machine) and the contents of the list file (FCHK.LOG)
Comparison between the checksum data of the list file and the result of checksum calculation
performed again for the list file
Comparison between the checksum data included in the list file and the result of checksum
calculation performed again for all the entire files that were transmitted (copied).
If list file comparison is successfully completed, a "0" return value will be passed to this
function as the program termination code. If list file comparison fails, this function receives a
return value that is not "0" and is abnormally terminated. In either case a history file is
generated (FCHKC.HIS is created in [FCHK.LOG file pathname]).
The history file is generated as track the process of comparing the transmitted (copied) file and
the list file.
The objective information to be compared in the files includes:
1) File size
2) Date and time of update
3) Transfer (copy) destination pathname (file name)
4) Number of transferred (copied) files
5) Checksum data of all the transferred (copied) files
6) Checksum data of list file
The checksum data of all the transferred (copied) files consists of the result in which each piece
of double-word data in all the objective files is XORed sequentially from beginning to end.
However, the checksum data of a list file is generated to obtain the sum of each double-word
contained in the list file, then a value is calculated that offsets the sum to zero.
Use this offset value as the checksum data.