You are looking for the PageWidth option in the OpenWrite function when initializing the stream.
PageWidth -> Infinity no linebreaking
I believe the default is PageWidth -> 80 (0--79)
If you output a newline character into your stream then you control where the lines are broken.
-----Original Message----- From: derivator [mailto:email@example.com] Sent: Thursday, April 10, 2014 2:10 AM Subject: Controlling breaking of lines in output of Write
When I use Write["file", expression], I find that if the expression is sufficiently long the output in "file" is broken into two or more lines. Usually this happens for expressions longer than 79 characters. Is it possible to change 79 to some other value, or control how the lines are broken in the output?