3 diff \- differential file comparator
12 tells what lines must be changed in two files to bring them
16 then a file in that directory with basename the same as that of
17 the other file is used.
18 If both files are directories, similarly named files in the
19 two directories are compared by the method of
25 If more than two file names are given, then each argument is compared
26 to the last argument as above.
31 to process similarly named subdirectories recursively.
32 When processing more than one file,
34 prefixes file differences with a single line
35 listing the two differing files, in the form of
41 flag causes this behavior even when processing single files.
43 The normal output contains lines of these forms:
63 The numbers after the letters pertain to
65 In fact, by exchanging `a' for `d' and reading backward
66 one may ascertain equally how to convert
80 are abbreviated as a single number.
82 Following each of these lines come all the lines that are
83 affected in the first file flagged by `<',
84 then all the lines that are affected in the second file
90 trailing blanks (spaces and tabs) to be ignored
91 and other strings of blanks to compare equal.
94 option causes all white-space to be removed from input lines
95 before applying the difference algorithm.
99 option prefixes each range with
101 and inserts a space around the
109 option produces a script of
113 commands for the editor
121 option produces a similar script,
124 in the opposite order. It may, however, be
125 useful as input to a stream-oriented post-processor.
129 option includes three lines of context around each
130 change, merging changes whose contexts overlap.
141 because the former are easier to distinguish when mixed.
144 flag displays the entire file as context.
148 option provides a unix-compatible unified diff.
149 This format is similar to that provided by
155 prefixes are not separated from the rest of the line by spaces,
156 and the file header is in the following format:
161 @@ -line,len +line,len @@
164 Except in rare circumstances,
166 finds a smallest sufficient set of file
178 Exit status is the empty string
186 Editing scripts produced under the
188 .BR -f " option are naive about"
189 creating lines consisting of a single `\fB.\fR'.
193 on directories, the notion of what is a text
194 file is open to debate.