Talk:Redirection (computing)

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I don't see any evidence that this is common in computing. Salvar (talk) 18:39, 23 March 2009 (UTC)

Test Program[edit]

You can test all kind of redirection with this little shell script:

 echo "This is stdout."
 echo "This is stderr." >&2


Is piping redirection? DG12 (talk) 17:01, 14 November 2011 (UTC)

Yes it is. Output from the first program is no longer going to the terminal, and input from the second program no longer comes from the terminal. —EncMstr (talk) 17:14, 14 November 2011 (UTC)

Bad analogue, someone with good English skills should rewrite[edit]

In the article

command1 | command2

was said to be equal to

command1 > tempfile
command2 < tempfile
rm tempfile

which it isn't, since the commands are executed in different subshells when a pipe is used, which means that the commands is usually executed in parallel and there is usually no temporary files created (or swap space used), just a file handle and a (usually) tiny buffer. Piping usually use much less memory then creating a temporary file and is faster. I'm guessing this is an old DOSism (in early MS/PC DOS was the given analogue correct). I'm not good enough with English to provide a better explanation, so I have only changed the wording from the two examples being "equal" to being "similar". But the analogue is still bad and might confuse someone. — Preceding unsigned comment added by Se mj (talkcontribs) 23:10, 1 December 2011 (UTC)

Done. (talk) 14:24, 9 February 2012 (UTC)