in reply to Re: Replace first blank line in a text file with headers.
in thread Replace first blank line in a text file with headers.

You can always change it ONLY on the first line, with linenumber $.

perl -pi -le 's/^\s*$/Name, City, State, Zip/ if $.==1' filename.txt

edit: Sorry, forgot the -l (without it, the line is replace-inserted without newline, and the next line with data does not start at the beginning of the next line)

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