open(FILE, $file) is fine, even with strict subs, but if you're concerned that some other sub in the same package might need simultaneous use of the same filehandle name, then you can do this:

sub mysub {
 my $fh = \do { local *FILE};
 open($fh, ">myfile")...
...
}
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Note that later versions of perl (5.6+ ?) will autovivify a scalar to a file handle so you can just do this:

sub mysub {
 open(my $fh, ">myfile")...
...
}
[download]