If it is a one-liner then your perl is probably simple enough to go into " rather than ' (just backlash any $vars or double quotes), so: 
export F="\t"
perl -F$F -line "munge(@F); print join($F, @F);" file

[download]
The join($F, @F) looks a bit evil, but hey.

Sadly, this doesn't work: 

F="\t" perl -F$F -line "munge(@F); print join($F, @F);" file

[download]
Presumably because the prefixed env var doesn't apply to the shell's expansion of the line.

Does anyone know a trick to make this (shorter) approach work?

In reply to Re: Does Perl 5 (or 6?) need another built-in variable for the -F switch? by jbert
in thread Does Perl 5 (or 6?) need another built-in variable for the -F switch? by japhy

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