diffmk(1)diffmk(1)NAMEdiffmk - mark changes between two different versions of a file
SYNOPSIS
prevfile currfile markfile
DESCRIPTION
compares the previous version of a file with the current version and
creates a file that includes ``change mark'' commands. prevfile is the
name of the previous version of the file and currfile is the name of
the current version of the file. generates markfile which contains all
the lines of the currfile plus inserted formatter ``change mark''
requests. When markfile is formatted, changed or inserted text is
shown by a character at the right margin of each line. The position of
deleted text is shown by a single
If the characters and are inappropriate, a copy of can be edited to
change them because is a shell script.
EXTERNAL INFLUENCES
International Code Set Support
Single- and multi-byte character code sets are supported.
EXAMPLES
A typical command line for comparing two versions of an file and gener‐
ating a file with the changes marked is:
can also be used to produce listings of C (or other) programs with
changes marked. A typical command line for such use is:
where the file contains:
The request can specify a different line length, depending on the
nature of the program being printed. The request is probably needed
only for C programs.
WARNINGS
Aesthetic considerations may dictate manual adjustment of some output.
does not differentiate between changes in text and changes in formatter
request coding. Thus, file differences involving only formatting
changes (such as replacing with in a text source file) with no change
in actual text can produce change marks.
Although unlikely, certain combinations of formatting requests can
cause change marks to either disappear or to mark too much. Manual
intervention may be required because the subtleties of various format‐
ting macro packages and preprocessors is beyond the scope of cannot
tolerate commands in its input (see tbl(1)), so any request that would
appear inside a range is silently deleted. The script can be changed
if this action is inappropriate, or can be run on two files that have
both been run through the preprocessor before any comparisons are made.
uses and thus has the same limitations on file size and performance
that may impose (see diff(1)). In particular the performance is non‐
linear with the size of the file, and very large files (well over 1000
lines) may take extremely long to process. Breaking the file into
smaller pieces may be advisable.
also uses the ed(1) editor. If the file is too large for error mes‐
sages may be embedded in the file. Again, breaking the file into
smaller pieces may be advisable.
SEE ALSOdiff(1), nroff(1).
diffmk(1)