Talk:True and false (commands)

Latest comment: 4 years ago by 82.2.238.102 in topic Is false required to return 1?

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I've removed the stub entry

Is there anything more to tell about true?

--Carpetsmoker 04:56, 29 July 2006 (UTC)Reply

Just possibly that in SCO (and probably other SYSV variants that /bin/true is (was) actually a 0 length file. With no "magic" in the header, the shell presumed it a script. Immediately hitting EOF and having executed no failing instructions, the shell returned "success" which is 0 which is "true."

Possibly too trivial--I'm new here.... —The preceding unsigned comment was added by 208.8.57.16 (talk) 14:27, August 21, 2007 (UTC)

Merge with false (unix)

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true(unix) and false(unix) should be merged, since they make antagon things. --Fixman (talk) 22:37, 2 April 2008 (UTC)Reply

You are an idiot. They are two different UNIX comands. --BrownGez (talk) 22:52, 31 May 2009 (UTC)Reply
I agree. true and false are two different commands with different meaning. Article should be splitted. --DaBler (talk) 22:44, 27 February 2010 (UTC)Reply

Why not same classical logic has 1=true and 0=false

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Investigate and tell —Preceding unsigned comment added by Foryourinfo (talkcontribs) 18:07, 27 July 2010 (UTC)Reply

Because, with apologies to Tolstoy, All successful program executions are alike, but each of up to 255 failed program executions may fail in their own fashion. 213.121.9.190 (talk) 19:19, 19 April 2018 (UTC)Reply

Setting variables with :

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I think this section is misleading. "It is also used as a no-op dummy command for side-effects such as assigning default values to shell variables through the ${parameter:=word} parameter expansion form.[2]". Looking at the reference, there's nothing about ${parameter:=word} and whilst that does set the value of the variable if it's empty, I don't believe this colon has anything to do with the null command (except that it's also a colon). rmwiseman (talk) 12:34, 8 August 2019 (UTC)Reply

Is false required to return 1?

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According to the standards here, the only requirement is for the return code to be non-zero. Linux seems to choose 1, as does the bash builtin, but on illumos (and Solaris?) it's 255. — Preceding unsigned comment added by 82.2.238.102 (talk) 21:56, 12 February 2020 (UTC)Reply