berkdiff(1) DG/UX 4.30 berkdiff(1)
NAME
berk_diff - Berkeley differential file and directory
comparator
SYNOPSIS
berkdiff [ -l ] [ -r ] [ -s ] [ -cefhn ] [ -biwt ] dir1
dir2
berkdiff [ -cefhn ] [ -biwt ] file1 file2
berkdiff [ -Dstring ] [ -biw ] file1 file2
DESCRIPTION
If both arguments are directories, berk_diff sorts the
contents of the directories by name, and then runs the
regular file berk_diff algorithm (described below) on text
files which are different. Binary files which differ,
common subdirectories, and files which appear in only one
directory are listed. Options when comparing directories
are:
-l long output format; each text file berk_diff is piped
through pr(1) to paginate it, other differences are
remembered and summarized after all text file
differences are reported.
-r causes application of berk_diff recursively to common
subdirectories encountered.
-s causes berk_diff to report files which are the same,
which are otherwise not mentioned.
-Sname
starts a directory berk_diff in the middle beginning
with file name.
When run on regular files, and when comparing text files
which differ during directory comparison, berk_diff tells
what lines must be changed in the files to bring them into
agreement. Except in rare circumstances, berk_diff finds a
smallest sufficient set of file differences. If neither
file1 nor file2 is a directory, then either may be given as
`-', in which case the standard input is used. If file1 is
a directory, then a file in that directory whose file-name
is the same as the file-name of file2 is used (and vice
versa).
There are several options for output format; the default
output format contains lines of these forms:
n1 a n3,n4
n1,n2 d n3
n1,n2 c n3,n4
Licensed material--property of copyright holder(s) Page 1
berkdiff(1) DG/UX 4.30 berkdiff(1)
These lines resemble ed commands to convert file1 into
file2. The numbers after the letters pertain to file2. In
fact, by exchanging `a' for `d' and reading backward one may
ascertain equally how to convert file2 into file1. As in
ed, identical pairs where n1 = n2 or n3 = n4 are abbreviated
as a single number.
Following each of these lines come all the lines that are
affected in the first file flagged by `<', then all the
lines that are affected in the second file flagged by `>'.
Except for -b, -w, -i or -t which may be given with any of
the others, the following options are mutually exclusive:
-e produces a script of a, c and d commands for the
editor ed, which will recreate file2 from file1.
In connection with -e, the following shell program
may help maintain multiple versions of a file.
Only an ancestral file ($1) and a chain of
version-to-version ed scripts ($2,$3,...) made by
berk_diff need be on hand. A `latest version'
appears on the standard output.
(shift; cat $*; echo '1,$p') | ed - $1
Extra commands are added to the output when
comparing directories with -e, so that the result
is a sh(1) script for converting text files which
are common to the two directories from their state
in dir1 to their state in dir2.
-f produces a script similar to that of -e, not useful
with ed, and in the opposite order.
-n produces a script similar to that of -e, but in the
opposite order and with a count of changed lines on
each insert or delete command. This is the form
used by rcsdiff(1).
-c produces a berk_diff with lines of context. The
default is to present 3 lines of context and may be
changed, e.g to 10, by -c10. With -c the output
format is modified slightly: the output beginning
with identification of the files involved and their
creation dates and then each change is separated by
a line with a dozen *'s. The lines removed from
file1 are marked with `- '; those added to file2
are marked `+ '. Lines which are changed from one
file to the other are marked in both files with
with `! '.
Changes which lie within <context> lines of each
Licensed material--property of copyright holder(s) Page 2
berkdiff(1) DG/UX 4.30 berkdiff(1)
other are grouped together on output. (This is a
change from the previous ``berk_diff -c'' but the
resulting output is usually much easier to
interpret.)
-h does a fast, half-hearted job. It works only when
changed stretches are short and well separated, but
does work on files of unlimited length.
-Dstring causes berk_diff to create a merged version of
file1 and file2 on the standard output, with C
preprocessor controls included so that a
compilation of the result without defining string
is equivalent to compiling file1, while defining
string will yield file2.
-b causes trailing blanks (spaces and tabs) to be
ignored, and other strings of blanks to compare
equal.
-w is similar to -b but causes whitespace (blanks and
tabs) to be totally ignored. E.g.,
``if ( a == b )'' will compare equal to
``if(a==b)''.
-i ignores the case of letters. E.g., ``A'' will
compare equal to ``a''.
-t will expand tabs in output lines. Normal or -c
output adds character(s) to the front of each line
which may screw up the indentation of the original
source lines and make the output listing difficult
to interpret. This option will preserve the
original source's indentation.
FILES
/tmp/d?????
/usr/lib/diffh for -h
/bin/diff for directory diffs
/bin/pr
SEE ALSO
cmp(1), cc(1), comm(1), diff(1), diff3(1), ued(1),
berk_diff3(1)
DIAGNOSTICS
Exit status is 0 for no differences, 1 for some, 2 for
trouble.
BUGS
Editing scripts produced under the -e or -f option are naive
about creating lines consisting of a single `.'.
Licensed material--property of copyright holder(s) Page 3
berkdiff(1) DG/UX 4.30 berkdiff(1)
When comparing directories with the -b, -w or -i options
specified, berk_diff first compares the files ala cmp, and
then decides to run the berk_diff algorithm if they are not
equal. This may cause a small amount of spurious output if
the files then turn out to be identical because the only
differences are insignificant blank string or case
differences.
Licensed material--property of copyright holder(s) Page 4