diffutils: Invoking diff
13 Invoking 'diff'
******************
The format for running the 'diff' command is:
diff OPTIONS... FILES...
In the simplest case, two file names FROM-FILE and TO-FILE are given,
and 'diff' compares the contents of FROM-FILE and TO-FILE. A file name
of '-' stands for the standard input.
If one file is a directory and the other is not, 'diff' compares the
file in the directory whose name is that of the non-directory. The
non-directory file must not be '-'.
If two file names are given and both are directories, 'diff' compares
corresponding files in both directories, in alphabetical order; this
comparison is not recursive unless the '--recursive' ('-r') option is
given. 'diff' never compares the actual contents of a directory as if
it were a file. The file that is fully specified may not be standard
input, because standard input is nameless and the notion of "file with
the same name" does not apply.
If the '--from-file=FILE' option is given, the number of file names
is arbitrary, and FILE is compared to each named file. Similarly, if
the '--to-file=FILE' option is given, each named file is compared to
FILE.
'diff' options begin with '-', so normally file names may not begin
with '-'. However, '--' as an argument by itself treats the remaining
arguments as file names even if they begin with '-'.
An exit status of 0 means no differences were found, 1 means some
differences were found, and 2 means trouble.
Menu