There's probably a more elegant way, but this works. 

@files = sort { my ($ad) = ( $a =~ /fwlog\.(\d+)\w+/ ); 
                my ($bd) = ( $b =~ /fwlog\.(\d+)\w+/ ); 
                $ad <=> $bd } @files;

print join "\n", @files;


OUTPUT:
fwlog.1Mar2005.gz
fwlog.2Mar2005.gz
fwlog.3Mar2005.gz
fwlog.4Mar2005.gz
fwlog.5Mar2005.gz
fwlog.6Mar2005.gz
fwlog.7Mar2005.gz
fwlog.8Mar2005.gz
fwlog.9Mar2005.gz
fwlog.14Mar2005.gz
fwlog.15Mar2005.gz
fwlog.16Mar2005.gz
fwlog.17Mar2005.gz
fwlog.18Mar2005.gz
fwlog.19Mar2005.gz
fwlog.20Mar2005.gz
fwlog.21Mar2005.gz

[download]

Update: I'm dumbfounded that so many have reccomended the Schwartzian for such a trivial sorting operation. Is the added complexity worth it for sorting such a small amount of data? Neither [id://JediWizard]'s nor [id://Tanktalus]'s code appear to even work correctly. (See Readmore). This is a case of over-zealous premature optimization if I've ever seen it.

Up-Update:Typos.

JediWizard's output: 
fwlogfwlog.14Mar2005.gz.Mar2005
fwlogfwlog.15Mar2005.gz.Mar2005
fwlogfwlog.16Mar2005.gz.Mar2005
fwlogfwlog.17Mar2005.gz.Mar2005
fwlogfwlog.18Mar2005.gz.Mar2005
fwlogfwlog.19Mar2005.gz.Mar2005
fwlogfwlog.1Mar2005.gz.Mar2005
fwlogfwlog.20Mar2005.gz.Mar2005
fwlogfwlog.21Mar2005.gz.Mar2005
fwlogfwlog.2Mar2005.gz.Mar2005
fwlogfwlog.3Mar2005.gz.Mar2005
fwlogfwlog.4Mar2005.gz.Mar2005
fwlogfwlog.5Mar2005.gz.Mar2005
fwlogfwlog.6Mar2005.gz.Mar2005
fwlogfwlog.7Mar2005.gz.Mar2005
fwlogfwlog.8Mar2005.gz.Mar2005
fwlogfwlog.9Mar2005.gz.Mar2005

[download]

And Tanktalus's: 

fwlog.9Mar2005.gz
fwlog.8Mar2005.gz
fwlog.7Mar2005.gz
fwlog.6Mar2005.gz
fwlog.5Mar2005.gz
fwlog.4Mar2005.gz
fwlog.3Mar2005.gz
fwlog.2Mar2005.gz
fwlog.21Mar2005.gz
fwlog.20Mar2005.gz
fwlog.1Mar2005.gz
fwlog.19Mar2005.gz
fwlog.18Mar2005.gz
fwlog.17Mar2005.gz
fwlog.16Mar2005.gz
fwlog.15Mar2005.gz
fwlog.14Mar2005.gz

[download]

In reply to Re: Sort on Number Embedded in String by friedo
in thread Sort on Number Embedded in String by Dru

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