From mboxrd@z Thu Jan 1 00:00:00 1970 From: doug@cs.dartmouth.edu (Doug McIlroy) Date: Thu, 07 Aug 2014 22:12:55 -0400 Subject: [TUHS] Unix taste Message-ID: <201408080212.s782CtwK007175@coolidge.cs.dartmouth.edu> Thanks, Norman, for reminding me of the actual pipe syntax in v3. This reinforces the title of one history item on Dennis's website: "Why Ken had to invent |". I'd suppressed all memory of the fact that in the pipeline ... > cmd > ... cmd had to be a single token. That was certainly not the intent of my original proposal. It is understandable, though, as a minimal hack to the existing shell syntax and its parser, which accepted occurrences of token anywhere in a command. The single-token rule meant that, if you wanted to supply an option to wc in the pipeline ls > wc > you couldn't write ls > wc -l > as one would expect, but instead had to write ls > "wc -l" > Yet a quoted "wc -l" as a bare command or (I suspect) as the first command in a pipeline would lead to "command not found". What a mess! Soon after, Ken was inspired to invent the | operator, lest he should have to describe an ugly duckling in public at an upcoming symposium in London. Is it possible that the ugliness of the token hack was the precipitating factor that gave us the sublime | ? But for the hack, perhaps we'd still be writing ls > wc > Doug