I have some code that does somthing like this: 
open FILE, "+<$filename";
undef $/;
$old_data = <FILE>;
#do some stuff
seek FILE, 0, 0;
print FILE $new_data;

[download]
This works fine, except when $new_data is smaller than $old_data. In that case, I get the end of $old_data left in my file, which isn't what I want. Is there a way I can either shrink the file to zero size instead of just seeking to the beginning, or tell perl to end the file at the current cursor position, ignoring everything after it? Or should I just give in and close the file and re-open it?

--
Ryan Koppenhaver, Aspiring Perl Hacker
"I ask for so little. Just fear me, love me, do as I say and I will be your slave."

In reply to read-write troubles by rlk

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