Probably the easiest way is to give Perl an argument, like this: 
cat file | perl -n0e 'BEGIN{$var = shift} #more code' myvar

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Then $var will contain the value 'myvar'. You might also use an environment variable accessible via the %ENV hash, like this: 
VAR=myvar; export VAR; cat file | perl -n0e 'BEGIN{$var = $ENV{VAR}} #
+more code'

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I hope this is a useful answer to your question.

In reply to Re: one line perl code by thelenm
in thread one line perl code by perlisfun

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