4 Mar
2024
4 Mar
'24
6 p.m.
my recollection is that awk and sed were contemporaneous.
On Sun, Mar 3, 2024 at 9:04 PM Marc Rochkind <mrochkind(a)gmail.com> wrote:
Will, here's my recollection, when I got to UNIX in late 1972 or thereabouts:
First, there was ed. grep and sed were derived from ed, so came along later. awk came
along way later.
There were only manual pages. You typed "man ed" and there it was. The man
pages were very accurate, very clear, and very authoritative. Many found them too
succinct, especially as UNIX got more popular, but all of us back in the day found them
perfect. Maybe you had to read the man page a few times to understand it, but at least
that's all you had to read. No need to hunt around for more documentation!
(Well, there was more documentation: The source code, which was all online. But reading
the ed source to understand regular expressions was impossible. It was in assembler, and
Ken was generating code on the fly as the expression was compiled.)
Also, it should be noted that ed produced a single error message: a question mark. No
wasting of teletype paper!
The motivation for learning regular expressions was that that's how you edited
files. ed was the only game in town.
(sh used a greatly restricted form of regular expressions, which were documented on the
sh man page.)
Marc Rochkind
On Sun, Mar 3, 2024 at 6:31 PM Will Senn <will.senn(a)gmail.com> wrote:
Hi All,
I was wondering, what were the best early sources of information for regexes and why did
folks need to know them to use unix? In my recent explorations, I have needed to have a
better understanding of them, so I'm digging in... awk's my most recent thing
and it's deeply associated with them, so here we are. I went to the bookshelf to find
something appropriate and as usual, I've traced to primary sources to some extent. I
started with Mastering Regular Expressions by Friedl, and I won't knock it (it's
one of the bestsellers in our field), but it's much to long for my personal taste and
it's not quite as systematic as I would like (the author himself notes that his
interests are less technical than authors preceding him on the subject). So, back to the
shelves... Bourne's, The Unix Environment, and Kernighan & Pike's, The Unix
Programming Evironment both talk about them in the context of grep, ed, sed, and awk.
Going further back, the Unix Programmer's Manual v7 - ed, grep, sed, awk...
After digging around it seems like folks needed regexes for ed, grep, sed and awk... and
any other utility that leveraged the wonderful nature of these handy expressions. Fine.
Where did folks go learn them? Was there a particularly good (succinct and accurate)
source of information that folks kept handy? I'm imagining (based on what I've
seen) that someone might cut out the ed discussion or the grep pages of the manual and
tape them to their monitors, but maybe I'm stooopid and they didn't need no
stinkin' memory device for regexes - surely they're intuitive enough that even a
simpleton could pick them up after seeing a few examples... but if that were really the
case, Friedl's book would have been a flop and it wasn't :). So seriously, if
you remember that far back - what was the definitive source of your regex knowledge and
what were the first motivators for learning them?
Thanks,
Will
--
My new email address is mrochkind(a)gmail.com