6 Sep
2017
6 Sep
'17
9:06 a.m.
One of the interesting thing that troff lled to in Unix was stderr!
Initially, Unix had stdin and stdout, but no stderr. We had a
phototypesetter that worked by flashing pictures of the various
letters on photosensitive paper. It came out in a roll that had to
be fed into a developer and when it emerged it had to be cut into
pages manually. Several months after we got the phototypesetter
somebody (The Hunt brothers?) cornered the market for silver, and the
cost of the developer shot through the roof. We were asked to cut
back on our use of the phototypesetter, and we tried to do so.One day,
I was attempting to print out a one-page document. I ran troff piped
into the phototypesetter and got out my roll of paper and fed it into
the developer. Out the other end came a page with only one line on
it (beautifully typeset): "cannot open input file xxx" A number of
others had similar experiences, and stderr was born...