common to both DIR1 and DIR2, or with the `not:' prefix, the ones
present in DIR1 and not in DIR2.
+It compares files by first comparing their sizes, hence goes
+reasonably fast.
+
+When looking for identical files, \fBfinddup\fP associates by default
+a group ID to every content, and prints it along the file names.
+
+Note that
+.B finddup DIR
+is the same as
+.B finddup -i DIR DIR
+
.SH "OPTIONS"
.TP
\fB-h\fR
\fB-d\fR
ignore files and directories starting with a dot
.TP
+\fB-0\fR
+ignore empty files
+.TP
\fB-c\fR
do not show which files from DIR2 corresponds to files from DIR1
+(hence, show only the files from DIR1 which have an identical twin in
+DIR2)
.TP
\fB-g\fR
-show the file group IDs (one group for each content)
+do not show the file group IDs
+.TP
+\fB-p\fR
+show progress information in stderr
.TP
\fB-r\fR
-shows the real path of the files
+show the real path of the files
+.TP
+\fB-i\fR
+files with same inode are considered as different
.SH "BUGS"
-The display is not sorted by groups.
+None known, probably many. Valgrind does not complain though.
+
+.SH "WISH LIST"
+
+The format of the output should definitely be improved. Not clear how.
+
+The comparison algorithm could definitely use some MD5 kind of
+signature. However, I doubt it would improve speed much.
+
+Their should be some fancy option to link two instances of the command
+running on different machines to reduce network disk accesses.
.SH "EXAMPLES"
-.nf
-.B finddup -c blah something
+
+.B finddup -cg blah something
.fi
-List files found in
-.B ./blah/
-which have a matching file with exact same content in
-.B ./something/
+List files found in \fB./blah/\fR which have a matching file with same
+content in \fB./something/\fR. Do not display the group IDs.
.P
-.B finddup ./sources not:./backup
+.B finddup sources not:/mnt/backup
.fi
-List all files found in
-.B ./sources/
-which do not have content-matching equivalent in
-.B ./backup.sources
+List all files found in \fB./sources/\fR which do not have
+content-matching equivalent in \fB/mnt/backup\fR.
.P
-.B finddup -g ./tralala ./cuicui | sort -n
+.B finddup tralala cuicui
.fi
List groups of files with same content which exist both in
-.B ./tralala/
-and
-.B ./cuicui/
+\fB./tralala/\fR and \fB./cuicui/\fR.
.SH "AUTHOR"