[Python-Dev] subprocess not escaping "^" on Windows

[Christian Tismer]

Ok, I thought only about Windows where people often use shell=True.
I did not see that as a Linux problem, too.

Not meant as a proposal, just loud thinking... :-)

But as said, the incomplete escaping is a complete mess.

Ciao -- Chris

On 07.01.18 19:54, Christian Tismer wrote:
> By "normal user expectations" I meant the behavior when the builtin commands
> were normal programs.
> 
> Using "shell=True" is everywhere recommended to avoid, and I believe
> we could avoid it by giving them replacements for build-ins.
> 
> But I don't care if the shell escaping is correct. And that is not
> trivial, either.
> 
> On 07.01.18 18:22, Guido van Rossum wrote:
>> On Sun, Jan 7, 2018 at 8:17 AM, Christian Tismer <tismer at stackless.com
>> <mailto:tismer at stackless.com>> wrote:
>>
>>     As a side note: In most cases where shell=True is found, people
>>     seem to need evaluation of the PATH variable. To my understanding,
>>
>>     >>> from subprocess import call
>>     >>> call(("ls",))
>>
>>     works in Linux, but (with dir) not in Windows. But that is misleading
>>     because "dir" is a builtin command but "ls" is not. The same holds for
>>     "del" (Windows) and "rm" (Linux).
>>
>>     So I thought that using shell=True was a good Thing on windows,
>>     but actually it is the start of all evil.
>>     Using regular commands like "git" works fine on Windows and Linux
>>     without the shell=True parameter.
>>
>>     Perhaps it would be a good thing to emulate the builtin programs
>>     in python by some shell=True replacement (emulate_shell=True?)
>>     to match the normal user expectations without using the shell?
>>
>>
>> That feels like a terrible idea to me. How do you define "normal user
>> expectations" here? If people want shell builtins they should just use
>> shell=True. (Also note IIUC there are several quite different shells
>> commonly used on Windows, e.g. PowerShell.)
>>
>> -- 
>> --Guido van Rossum (python.org/~guido <http://python.org/~guido>)
> 
> 


-- 
Christian Tismer-Sperling    :^)   tismer at stackless.com
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