tilly, your version: 

perl -pi.bak -e 'BEGIN{$/=$u}s//\n/' foo*

[download]

Works fine with 5.00503, but with 5.6.0 it appends an extra newline to the file: 

$ cat > XXX 
1
2
3
$ cp XXX fxx
$ perl5.00503 -pi.bak -e 'BEGIN{$/=$u}s/^/\n/' fxx*
$ cat fxx

1
2
3
$ cp XXX fxx
$ perl5.6.0 -pi.bak -e 'BEGIN{$/=$u}s/^/\n/' fxx*
$ cat fxx

1
2
3

$

[download]

Curious.

In reply to Re: Re (tilly) 2: Yet another one-liner by danger
in thread Yet another one-liner by wardk

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