Shmuel (Seymour J.) Metz <spam...@library.lspace.org.invalid> writes:
> In <kmqmtu$g5b$
1...@dont-email.me>, on 05/13/2013
> at 08:49 AM, Peter Flass <Peter...@Yahoo.com> said:
>
>>Until laser printers came in, more so than dot-matrix printers, you
>>were limited by the characters your printer could generate.
>
> LASER printers *are* dot matrix printers. More to the point,
> photocompositers were available before then. When did troff become
> available?
From wikipedia under "troff":
troff can trace its origins back to a text formatting program called
RUNOFF, written by Jerome H. Saltzer for MIT's CTSS operating system in
the mid-1960s. (The name allegedly came from the phrase at the time,
I'll run off a document.)
Bob Morris ported it to the GE 635 architecture and called the program
roff (an abbreviation of runoff). It was rewritten as rf for the PDP-7,
and at the same time (1969), Doug McIlroy rewrote an extended and
simplified version of roff in the BCPL programming language.
The first version of Unix was developed on a PDP-7 which was sitting
around Bell Labs. In 1971 the developers wanted to get a PDP-11 for
further work on the operating system. In order to justify the cost for
this system, they proposed that they would implement a
document-formatting system for the AT&T patents division. This first
formatting program was a reimplementation of McIllroy's roff, written by
Joe F. Ossanna.
When they needed a more flexible language, a new version of roff called
nroff (newer 'roff' ) was written. It had a much more complicated
syntax, and provided the basis for all future versions. When they got a
Graphic Systems CAT phototypesetter, Ossanna wrote a version of nroff
that would drive it. It was dubbed troff, for typesetter 'roff'.[1] As
such, the name troff is pronounced /ˈtiː.rɒf/ rather than */ˈtrɒf/.
With troff came nroff (they were actually almost the same program),
which was for producing output for line printers and character
terminals. It understood everything troff did, and ignored the commands
which were not applicable (e.g. font changes).
Unfortunately, Ossanna's troff was written in PDP-11 assembly language
and produced output specifically for the CAT phototypesetter. He rewrote
it in C, although it was now 7000 lines of uncommented code and still
dependent on the CAT. As the CAT became less common, and was no longer
supported by the manufacturer, the need to make it support other devices
became a priority. Unfortunately, Ossanna died before this task was
completed.
So, Brian Kernighan took on the task of rewriting troff. The newly
rewritten version produced a device-independent code which was very easy
for postprocessors to read and translate to the appropriate printer
codes. Also, this new version of troff (often called ditroff for device
independent troff) had several extensions, which included drawing
functions.[2] The program's documentation defines the output format of
ditroff, which is used by many modern troff clones like GNU groff.
-- Patrick