DIFFMK(1)DIFFMK(1)NAMEdiffmk - mark differences between versions of a troff input file
SYNOPSISdiffmk oldfile newfile markedfile
DESCRIPTIONdiffmk compares two versions of a file and creates a third version that
includes "change mark" (.mc) commands for nroff(1) and troff(1). old‐
file and newfile are the old and new versions of the file. diffmk gen‐
erates markedfile, which, contains the text from newfile with troff(1)
"change mark" requests (.mc) inserted where newfile differs from old‐
file. When markedfile 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 *.
See largefile(5) for the description of the behavior of diffmk when
encountering files greater than or equal to 2 Gbyte ( 2^31 bytes).
Example 1 An example of the diffmk command.
diffmk can also be used in conjunction with the proper troff requests
to produce program listings with marked changes. In the following com‐
example% diffmk old.c new.c marked.c ; nroff reqs marked.c | pr
the file reqs contains the following troff requests:
which eliminate page breaks, adjust the line length, set no-fill mode,
ignore escape characters, and turn off hyphenation, respectively.
If the characters | and * are inappropriate, you might run markedfile
through sed(1) to globally change them.
SEE ALSOdiff(1), nroff(1), sed(1), troff(1), attributes(5), largefile(5)BUGS
Aesthetic considerations may dictate manual adjustment of some output.
File differences involving only formatting requests may produce unde‐
sirable output, that is, replacing .sp by .sp 2 will produce a "change
mark" on the preceding or following line of output.
Sep 14, 1992 DIFFMK(1)