G'day slugger415,

The effect you're seeing with the four characters of ".mp3" overwriting the first four characters of "newfile", generally indicates an embedded carriage return. Such as: 

$ perl -e 'my $x = "newfile"; my $y = "\r.mp3"; print "$x$y\n"'
.mp3ile

[download]

You haven't shown your whole code, or cut it down to something that reproduces the behaviour (see SSCCE).

I suspect you haven't used the strict and warnings pragmata: they're certainly not included with the code you posted.

Your $str appears to be a package variable: action-at-a-distance is a possibility.

Interspersing \n and $/ is questionable. Why are you doing this?

— Ken

In reply to Re: Strange behavior with STDIN by kcott
in thread Strange behavior with STDIN by slugger415

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