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Re: Which shell and how to get started handling arguments

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 Kaz Kylheku <643-408-1753@kylheku.com>:
> On 2024-04-15, Helmut Waitzmann <nn.throttle@xoxy.net> wrote:
>>  Compare (using GNU ls) with Christians well‐behaving "ls": 
>>
>>
>>    touch -- foo -l
>>
>>    $ ls foo -l
>>    -rw------- 1 helmut helmut 0 Apr 15 15:28 foo
>
> touch deviates in the first place; omit the -- and you get 
>
>
>   $ touch foo -l
>   touch: invalid option -- 'l'
>
> That's crazy. foo is a non-option argument, so the options 
> have ended at that point. 
>

 Yes, that's the same problem like with GNU "ls".  (I decided to 
 silently avoid it by making use of the end‐of‐option marker 
 without commenting it.) 


> I see where it is documented in "2 Common options" (Coreutils 
> manual): 
>
>
>   Normally options and operands can appear in any order, and
>   programs act as if all the options appear before any operands.
>   For example, ‘sort -r passwd -t :’ acts like ‘sort -r -t :
>   passwd’, since ‘:’ is an option-argument of -t. However, if
>   the POSIXLY_CORRECT environment variable is set, options must
>   appear before operands, unless otherwise specified for a
>   particular command.
>

 If I understand the last sentence correctly, setting the 
 POSIXLY_CORRECT environment variable forces the GNU utilities to 
 stop option processing before the first non‐option argument 
 (i. e. an argument beginning not with a "-") as if that argument 
 had been preceded by the end‐of‐option argument "--". 


> It is disingenous to call it "POSIXly correct", because in fact 
> the POSIX rules are how everyone understands it and how other 
> implementors of utilities implement it. (Does anyone else do 
> this crazy thing?) 
>
>
> If all the vendors feature a given extension, so that it is 
> portable, but POSIX refuses to adopt it, then, sure: the mode 
> which takes the extension away can be flippantly called "POSIXly 
> correct". 
>

 Maybe my knowledge of the English language is not good enough to 
 understand you correctly.  Under the premise, that the 
 POSIXLY_CORRECT environment variable has been set, do you see the 
 GNU utilities behaving in any different way from what is the 
 behavior specified by POSIX? 


> Also the claim "options must appear before operands [in POSIX]" 
> is misleading, because "must" is usually interpreted as an 
> imposed requirement, which can be violated and diagnosed. But in 
> fact it is *logically* impossible for options to appear 
> elsewhere because arguments that look like options placed in the 
> non-option part of the command line are operands. It's the 
> logical "must", not the reuqirements "must". 
>

 The GNU manual does not say "in POSIX" but says "if the 
 POSIXLY_CORRECT environment variable is set", but otherwise I 
 agree with you.  This is, why I recommend to not make use of the 
 GNU behavior of looking for options right of the first non‐option 
 operand when neither the end‐of‐option marker is used nor the 
 POSIXLY_CORRECT environment variable has been set, but rather 
 always put any options (if present) first, then – regardless of 
 whether any options are actually present – in any case supply the 
 end‐of‐option marker ("--") and finally any non‐option operands.  
 This way both, POSIX utilities and GNU utilities, will behave the 
 same, even, if the POSIXLY_CORRECT environment variable happens 
 not to be set. 

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Which shell and how to get started handling arguments James Harris <james.harris.1@gmail.com> - 2024-04-15 13:22 +0100
  Re: Which shell and how to get started handling arguments Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-04-15 16:03 +0200
    Re: Which shell and how to get started handling arguments Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-04-15 16:34 +0200
  Re: Which shell and how to get started handling arguments Christian Weisgerber <naddy@mips.inka.de> - 2024-04-15 13:35 +0000
    Re: Which shell and how to get started handling arguments Helmut Waitzmann <nn.throttle@xoxy.net> - 2024-04-15 23:03 +0200
      Re: Which shell and how to get started handling arguments Kaz Kylheku <643-408-1753@kylheku.com> - 2024-04-16 01:14 +0000
        Re: Which shell and how to get started handling arguments Helmut Waitzmann <nn.throttle@xoxy.net> - 2024-04-16 22:23 +0200
  Re: Which shell and how to get started handling arguments Ben Bacarisse <ben.usenet@bsb.me.uk> - 2024-04-15 15:45 +0100
  Re: Which shell and how to get started handling arguments Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2024-04-15 15:06 +0000
    Re: Which shell and how to get started handling arguments Christian Weisgerber <naddy@mips.inka.de> - 2024-04-15 15:36 +0000
      Re: Which shell and how to get started handling arguments gazelle@shell.xmission.com (Kenny McCormack) - 2024-04-15 17:38 +0000
        Re: Which shell and how to get started handling arguments Kaz Kylheku <643-408-1753@kylheku.com> - 2024-04-15 17:57 +0000
      Re: Which shell and how to get started handling arguments Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2024-04-15 20:37 +0000
    Re: Which shell and how to get started handling arguments Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-04-15 14:31 -0700
      Re: Which shell and how to get started handling arguments Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2024-04-16 10:19 +0200
      Re: Which shell and how to get started handling arguments Christian Weisgerber <naddy@mips.inka.de> - 2024-04-16 11:11 +0000
        Re: Which shell and how to get started handling arguments Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-04-16 11:54 -0700
          Re: Which shell and how to get started handling arguments gazelle@shell.xmission.com (Kenny McCormack) - 2024-04-16 19:59 +0000
            Re: Which shell and how to get started handling arguments Christian Weisgerber <naddy@mips.inka.de> - 2024-04-16 21:57 +0000
        Re: Which shell and how to get started handling arguments Kaz Kylheku <643-408-1753@kylheku.com> - 2024-04-16 20:45 +0000
          Re: Which shell and how to get started handling arguments Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-04-16 16:38 -0700
        Re: Which shell and how to get started handling arguments Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-04-17 00:52 +0000
          Re: Which shell and how to get started handling arguments gazelle@shell.xmission.com (Kenny McCormack) - 2024-04-17 09:02 +0000
          Re: Which shell and how to get started handling arguments Christian Weisgerber <naddy@mips.inka.de> - 2024-04-17 14:23 +0000
  Re: Which shell and how to get started handling arguments Helmut Waitzmann <nn.throttle@xoxy.net> - 2024-04-15 23:49 +0200
  Re: Which shell and how to get started handling arguments Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-04-15 22:20 +0000

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