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Re: Bash true/false builtings undocumented? "false" not working?

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On Fri, Aug 17, 2018 at 06:46:54PM +1000, Zenaan Harkness wrote:
> 1)
> Bash man page largely fails to document the true and false builtins
> AFAICT, except for this sentence just under the heading
> "^SHELL BUILTIN COMMANDS":
> 
>  The :, true, false, and test builtins do not accept options and do
>  not treat -- specially.
> 
> But whilst the subsequent list of Bash builtin commands DOES include
> entries for ":" (the very first entry) and "test", it appears to fail
> to include entries for "true" and for "false".
> 
> This would not matter so much except for the following:
> 
> 
> 2)
> Why is executing "false" prior to testing it's output, apparently
> differen to executing "false" in a pipeline, e.g.:
> 
> $ false
> $ test $? && echo ok || echo error $?
> ok
> $ false blah
> $ test $? && echo ok || echo error $?
> ok
> $ false --
> $ test $? && echo ok || echo error $?
> ok
> $ true
> $ test $? && echo ok || echo error $?
> ok
> $ true && echo ok || echo error $?
> ok
> $ false && echo ok || echo error $?
> error 1
> $ false blah && echo ok || echo error $?
> error 1
> $ false 2 && echo ok || echo error $?
> error 1
> $ false -- && echo ok || echo error $?
> error 1
> $ builtin false -- && echo ok || echo error $?
> error 1
> $ builtin false --
> $ test $? && echo ok || echo error $?
> ok
> $ which false
> /bin/false
> $ /bin/false
> $ test $? && echo ok || echo error $?
> ok
> 
> 
> 
> The above results are perplexing me, and frustratingly
> inconsistent!
> 
> For example, "man false" says inter alia:
> 
> NAME  false - do nothing, unsuccessfully
> …
> DESCRIPTION  Exit with a status code indicating failure.
> 
> 
> The descriptions suggests that /bin/false ought work outside of a
> pipeline in the same as way inside a pipeline - vhy, is, eet, not,
> so?
> 
> 
> TIA,


Could it be that the reason this does not work from the shell prompt
as I expect, is perhaps that my command prompt is successfully
running a command in between, and therefore hiding all error codes?

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Bash true/false builtings undocumented? "false" not working? Zenaan Harkness <zenaan@freedbms.net> - 2018-08-17 10:50 +0200
  Re: Bash true/false builtings undocumented? "false" not working? Zenaan Harkness <zenaan@freedbms.net> - 2018-08-17 11:00 +0200
  Re: Bash true/false builtings undocumented? "false" not working? Nicolas George <george@nsup.org> - 2018-08-17 11:00 +0200
    Re: Bash true/false builtings undocumented? "false" not working? Zenaan Harkness <zenaan@freedbms.net> - 2018-08-17 11:30 +0200
    Re: Bash true/false builtings undocumented? "false" not working? Zenaan Harkness <zenaan@freedbms.net> - 2018-08-17 11:40 +0200
      Re: Bash true/false builtings undocumented? "false" not working? Nicolas George <george@nsup.org> - 2018-08-17 11:40 +0200
      Re: Bash true/false builtings undocumented? "false" not working? <tomas@tuxteam.de> - 2018-08-17 12:20 +0200
      Re: Re: Bash true/false builtings undocumented? "false" not working? Clive Standbridge <list-user@tgstandbridges.plus.com> - 2018-08-17 14:10 +0200
        Re: Re: Bash true/false builtings undocumented? "false" not working? <tomas@tuxteam.de> - 2018-08-17 15:40 +0200
      Re: Bash true/false builtings undocumented? "false" not working? Greg Wooledge <wooledg@eeg.ccf.org> - 2018-08-17 14:30 +0200
        Re: Bash true/false builtings undocumented? "false" not working? <tomas@tuxteam.de> - 2018-08-17 15:50 +0200
          Re: Bash true/false builtings undocumented? "false" not working? Greg Wooledge <wooledg@eeg.ccf.org> - 2018-08-17 16:20 +0200
            Re: Bash true/false builtings undocumented? "false" not working? <tomas@tuxteam.de> - 2018-08-17 16:40 +0200
              Re: Bash true/false builtings undocumented? "false" not working? Zenaan Harkness <zenaan@freedbms.net> - 2018-08-18 01:10 +0200
        Re: Bash true/false builtings undocumented? "false" not working? Zenaan Harkness <zenaan@freedbms.net> - 2018-08-18 01:30 +0200
  Re: Bash true/false builtings undocumented? "false" not working? <tomas@tuxteam.de> - 2018-08-17 11:30 +0200
    Re: Bash true/false builtings undocumented? "false" not working? Zenaan Harkness <zenaan@freedbms.net> - 2018-08-17 11:40 +0200
      Re: Bash true/false builtings undocumented? "false" not working? <tomas@tuxteam.de> - 2018-08-17 11:50 +0200
        Re: Bash true/false builtings undocumented? "false" not working? tomas@tuxteam.de - 2018-08-17 12:00 +0200
      Re: Bash true/false builtings undocumented? "false" not working? Stefan Krusche <linux@stefan-krusche.de> - 2018-08-23 15:00 +0200
        Re: Bash true/false builtings undocumented? "false" not working? <tomas@tuxteam.de> - 2018-08-23 16:30 +0200

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