Who needs pipes?

B <<< $(A)
or: C

6
By: asg0451
2009-08-30 20:20:18

What Others Think

Wow, that's cool! I liked it!
danpos · 524 weeks and 5 days ago
Here documents are cool, but I think pipes win the fewest characters race. A|B
bwoodacre · 524 weeks and 5 days ago
@bwoodacre However the outcomes are slightly different. The "here document" concatenates A's output into a single line, whereas piping leaves A's output untouched.
flatcap · 524 weeks and 5 days ago
bash specific, useful for construct like: while read line; do var=line; done < $(command) echo "$var" A < <(B)
remil · 524 weeks and 4 days ago
sry, should be ... done < <(command) also useful construct diff <(cmd1) <(cmd2)
remil · 524 weeks and 4 days ago
@flatcap you are right! I keep forgetting that here documents turn a file into *arguments* for the command not standard input. Makes sense since there shouldn't be two ways to do the same thing.
bwoodacre · 524 weeks and 4 days ago
Sorry, what I just said is wrong. :-( http://www.gnu.org/software/bash/manual/bashref.html#Redirections
bwoodacre · 524 weeks and 4 days ago
I can think of at least one occasion where this will be useful: I SSH into a server from a phone that doesn't have the pipe character.
flipouk · 524 weeks and 3 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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