In addition to what Corion has imparted; once you understand what was causing the error - here is a one-liner you may use that echoes input to filename.txt and stops when a blank line is entered:

perl -pe "last if /^\s*$/" > filename.txt

[download]

In reply to Re: uninitialized value $_ by shadowsong
in thread uninitialized value $_ by Anonymous Monk

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