Another way: 
    perl -lpe '$\=(eof)?$/:","' file

[download]

Update: or this 

    perl -l54pe '$\=$/if+eof'   file

[download]

--
John.

In reply to Re: perl 1-liner to join a list? by jmcnamara
in thread perl 1-liner to join a list? by bfdi533

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