Here is a one-liner that reads a file in paragraph mode and then removes newlines if they terminate a line longer than or equal to some limit (in this case 40): 
    perl -00 -lpe 's/(.{40})\n/$1 /g' file

[download]

--
John.

In reply to Re: Single newline removal when line exceeds x characters by jmcnamara
in thread Single newline removal when line exceeds x characters by tomdyson

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