BCMP - block mode file compare.
Syntax:
BCMP file1 file2 [options]
Files=number +Gfrc
Name=element Size=N
(+|-)Verbose
Options:
- file1 file2
- are two files that you want to compare.
- Files=number
- is used with the +Gfrc option when you want to compare
multi-file GFRC files. By default, +Gfrc stops comparing
files at the first logical end-of-file. Files=number says
that the comparison should continue until BCMP has
compared "number" logical files or has reached
the physical end of the file. The given
"number" must be 1 or greater.
- +Gfrc
- compares the files using GFRC format information. BCMP
only compares the portions of each llink encompassed by
the block length in the BCW. BCMP checks the block serial
numbers of each BCW for validity, and also checks the
block length (which must be less than 320 words).
Comparison stops at the first logical end-of-file, unless
you also specify Files=number. You cannot use +Gfrc with
Name=.
- Name=element
- compares only the named element. In this case, both files
should be hstar files that contain the named element.
BCMP compares all sectors of the element including the
DCW block and any relocation blocks, if present. You
cannot use Name= with +Gfrc.
- Size=N
- only compares the first N llinks of the files (where N is
a positive integer). If either file is less than N llinks
long, BCMP uses the minimum size of the two files.
- +Verbose
- lists the sector and word offset for each word where the
files differ. The default is just to report a count of
the words that did not match. If you specify +Gfrc,
+Verbose reports differences using the format:
GFRC file #n, llink 0n word 000n: X != Y
where X and Y are 36-bit words given in octal.
- -Verbose
- suppresses the equality message if the contents compare
equal. The default action is to print an equality
message.
Description:
BCMP lets you compare two files to see if they are equal.
Probably the most common use would be to see if two executable
programs are identical (for example, if you want to see if two
versions of a program really are different). Using the Name=
option, you can compare individual elements of Hstar files.
Normally, you would not use BCMP on text files; use DIFF
instead. See "expl diff" for
more on DIFF.
BCMP performs a simple sector-by-sector comparison. It works
on a yes/no basis; either the sectors are identical or they
aren't. With +Verbose, BCMP shows the machine words where the
sectors differ.
BCMP sets the switch word to indicate the result of the
comparison. If an error occurs (for example, one of the files
cannot be found), bits 18-26 are all turned on. Otherwise bits 18
to 24 are turned off. Bit 25 is turned on if at least one pair of
words did not compare equal. Bit 26 is turned on if one of the
files or Hstar elements is smaller than the other.
Copyright © 1996, Thinkage Ltd.