[comp.os.vms] Checksum of files.

T_WADE@CSVAX.UCD.HEA.IRL (08/19/87)

If you are getting checksums for image (.EXE) files, then you should use
the /IMAGE qualifier of the CHECKSUM command. This causes CHECKSUM to
perform a section-by-section checksum with an overall checksum at the
end. Various things like link date/time are NOT included in  the checksum,
so (as far as I know) only the program data and code is checked. I did a
CHECKSUM/IMAGE on the LOGINOUT and SHOW files for three of our systems
(780, 750 and a Common system disk for a cluster), and I got the same
values for both in all cases. The values are given below. Running the
PATCH utility on a program (without making any changes) will not change
the checksum/image, nor will relinking the code.

The CHECKSUM/IMAGE command will output its results to the screen, but will
also set the symbol CHECKSUM$CHECKSUM as a decimal string.

LOGINOUT    07E3E8B4
SHOW        2A04A046

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