[ILUG] Re: sed question

[Brendan Kehoe]

> "first" is also on the first line of the input file. Apart from that it works
> fine, thanks. Does anyone know a one-liner sed/awk/perl to add a blank line to
> the start of a file? It seems to work fine if I add a blank line.
>   

In a single step?  Aside from

    #!/bin/sh
    echo > new-"$1"
    cat "$1" >> new-"$1"
    mv "$1" old-"$1"
    mv new-"$1" "$1"

maybe for awk try either

    awk '{if(NR==1) print ""; print;}'
    awk 'BEGIN{print ""} {print;}'

or perl

    perl -e 'print "\n"; while (<>) { print $_; }'
    perl -e 'print "\n"; print while <>;'

?  I'm sure there are great terse ways to do the same in each (and in 
sed, which I've never obsessed on enough).

Hope this helps,
B