If you are simply passing through the file editing it then a common Perl idiom is to use inplace edit thus: 

local @ARGV = ('nameOfFileToEdit');
local $^I = '.bak'; # extension for backup version of file

while (<>)
    {
    #line read is in $_
    print "new state of line\n"; # write updated line
    }

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DWIM is Perl's answer to Gödel

In reply to Re: open file for read/write by GrandFather
in thread open file for read/write by Anonymous Monk

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