Unsurprisingly, there's already a module on CPAN to handle the temp-file maneuvers: 
use IO::AtomicFile;

# Write a temp file, and have it install itself when closed:
my $FH = IO::AtomicFile->open("bar.dat", "w");
print $FH "Hello!\n";
$FH->close || die "couldn't install atomic file: $!";

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In reply to Re: Replacing a string in a file by simonm
in thread Replacing a string in a file by Avi

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