DIFFMK(1)

NAME
diffmk - mark differences between files

SYNOPSIS
diffmk [- []] [ filename1] [ filename2] [ filename3]

DESCRIPTION
diffmk compares two versions of a file and creates a third file that includes ``change mark'' requests for nroff or troff. filename1 and filename2 are the old and new versions of the file, respectively. diffmk generates filename3, which contains the lines of filename2 plus inserted formatter ``change mark'' requests. When filename3 is formatted, changed or inserted text is shown by | at the right margin of each line. The position of deleted text is shown by a single asterisk (*).

In addition, diffmk can be used to produce listings of C (or other) programs with changes marked. A typical command line for such use is
    diffmk old.c new.c tmp; nroff macs tmp
where the file contains
    .pl 1
    .ll 77
    .nf
    .eo
    .c2 `
The request might specify a different line length, depending on the nature of the program being printed. The and requests are probably needed only for C programs.

Where diffmk encounters [-] it uses the standard input.

BUGS
Aesthetic considerations may dictate manual adjustment of some output. File differences involving only formatting requests may produce undesirable output, i.e., replacing by will produce a ``change mark'' on the preceding or following line of output.

SEE ALSO
nroff(1), troff(1)