Re: rename files with mtime

[Narveson]

You do realize, I trust, that your program does not rename any files?

$file =~ s/\d+/$datestamp/ changes the contents of your variable $file. To use your own example, if $file contains maillog.1.gz and the datestamp is 20090213, then after the substitution $file will contain maillog.20090213.gz. The file on disk, however, is still named maillog.1.gz.

You are wise to be printing the outcome of the substitution so that you can review it. Assuming you are satisfied with your printout, how are you going to rename the file? In order to follow the template for rename, which is

rename OLDNAME,NEWNAME

you'll need to declare a second variable. The idiomatic way is

(my $new_name = $file) =~ s/\d+/$datestamp/;

after which you can say

rename $file, $new_name;

[grinder]

Speaking of idioms...

after which you can say

rename $file, $new_name;

The following idiom helps prevents renaming disasters:

rename $file, $new_name unless -e $new_name;

That is, don't rename a file if it would cause an existing file to be unlinked. It's easier to fix up the mess of a file that hasn't been renamed than one that no longer exists...