diffmk(1)						      General Commands Manual							 diffmk(1)

NAME

       diffmk - 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  con-
       tains 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 generating 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 formatting 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 messages may be embedded in  the  file.	 Again,  breaking  the	file  into
       smaller pieces may be advisable.

SEE ALSO

       diff(1), nroff(1).

																	 diffmk(1)