python 2.7.12 on Linux behaving differently than on Windows

Nathan Ernst nathan.ernst at gmail.com
Tue Dec 6 17:35:20 EST 2016


One other consideration in regards to globbing in the argument list:
there's a static limit to the byte length of argv. On windows, it's 8191
bytes (I'm assuming a null-terminator brings that to 8192, which is a weird
2**13). For Linux, as of kernal 2.6.25, apparently, the limit is 131072
bytes, an equally odd choice of 2**17 bytes.

I'm not sure if globs directly to commands bypass these restrictions, but
I've seen real world issues with build systems with thousands of files that
attempted to pass all dependencies to a target that blew up spectacularly
(one of the reasons cl & link on windows accept argument files as input
instead of just command line arguments).

Regards,
Nate

On Tue, Dec 6, 2016 at 4:24 PM, Chris Angelico <rosuav at gmail.com> wrote:

> On Wed, Dec 7, 2016 at 8:46 AM, Cameron Simpson <cs at zip.com.au> wrote:
> > Nothing prevents you writing an extremely simple shell yourself you
> know. It
> > needn't expand anything. _Or_ you could have it adopt the inverse
> > convention: expand nothing unless asked. Eg:
> >
> >  cp G:*.c
> >
> > to cause "*.c" to get expanded. Of course, because the various
> executables
> > don't feel any burden to implement globbing you may run into some
> impedence
> > mismatch.
>
> I actually have something like this in one application's inbuilt
> command executor - it does globbing ONLY if the parameter starts with
> a question mark (eg "?*.c" will glob "*.c" in that directory). It's
> deliberate, but frankly, it ends up annoying more often than not. I'm
> considering switching to a more normal way of doing it.
>
> ChrisA
> --
> https://mail.python.org/mailman/listinfo/python-list
>


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