The flags work without the command line, too. The following will convert any files specified on the command line to all caps. 
#!/usr/bin/perl -w -i.bak -p

$_ = uc;

[download]
In fact, there was an Obfuscated Perl contest entry a while back that does DOS-to-Unix conversions using only command line switches on the shebang line.

xoxo,
Andy 

# Andy Lester  http://www.petdance.com  AIM:petdance
%_=split';','.; Perl ;@;st a;m;ker;p;not;o;hac;t;her;y;ju';
print map $_{$_}, split //,
'andy@petdance.com'

In reply to Re: Re: converting files in place by petdance
in thread In-place editing of files (was: general perl question) by cghost23

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