Casio PA-2400W - Manual (Page 75)

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8.6.2 Comparison by List File
With this command the following comparison will be made:


Comparison between the file information transferred (copied) by the PA-2400W (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 return value “0” will be passed to this command as
the program termination code. If list file comparison fails, this command 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.