rename − renames multiple files
rename [ −v ] [ −n ] [ −f ] perlexpr [ files ]
"rename" renames the filenames supplied according to the rule specified as the first argument. The perlexpr argument is a Perl expression which is expected to modify the $_ string in Perl for at least some of the filenames specified. If a given filename is not modified by the expression, it will not be renamed. If no filenames are given on the command line, filenames will be read via standard input.
For example, to rename all files matching "*.bak" to strip the extension, you might say
rename 's/\.bak$//' *.bak
To translate uppercase names to lower, you’d use
rename 'y/A−Z/a−z/' *
Verbose: print names of files successfully renamed.
No Action: show what files would have been renamed.
Force: overwrite existing files.
No environment variables are used.
If you give an invalid Perl expression you’ll get a syntax error.
The original "rename" did not check for the existence of target filenames, so had to be used with care. I hope I’ve fixed that (Robin Barker).