"\cJ" is CTRL-J ("Control J"), which is what ASCII uses for "\n". "\cM" is CTRL-M, which is what ASCII uses for "\r". (Old Macs claim to be ASCII but get these two associations backward.)
You might want to read a recent related rant of mine: Re^4: Line Feeds (rumor control)
In reply to Re^2: line breaks in textarea; end of line characters? (a rant)
by tye
in thread line breaks in textarea; end of line characters?
by inblosam
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