From: Eric Blake <eblake@redhat.com>
To: cygwin@cygwin.com
Subject: Re: Command line processing in dcrt0.cc does not match Microsoft parsing rules
Date: Thu, 05 Sep 2019 19:05:00 -0000 [thread overview]
Message-ID: <0037aca6-e714-4e0a-53b8-18bbc582662a@redhat.com> (raw)
In-Reply-To: <MWHPR21MB0845282E7582DC95ADF0F140B9BB0@MWHPR21MB0845.namprd21.prod.outlook.com>
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On 9/5/19 1:31 PM, Stephen Provine via cygwin wrote:
> My mistake - I'm very aware of the quoting rules, yet in my test script for this
> scenario I forgot to quote the arguments. However, if POSIX rules are being
> implemented, there is still something I didn't expect. Here's my bash script:
>
> #!/bin/bash
> echo "$1"
> echo "$2"
> echo "$3"
>
> And I invoke it like this from a Windows command prompt:
>
> C:\> bash -x script.sh foo bar\"baz bat
> + echo foo
> foo
> + echo 'bar\baz bat'
> bar\baz bat
> + echo ''
>
> Not expected.
Why not? That obeyed cmd's odd rules: The moment you have a " in the
command line, that argument continues until end of line or the next "
(regardless of how many \ precede the ").
https://blogs.msdn.microsoft.com/twistylittlepassagesallalike/2011/04/23/everyone-quotes-command-line-arguments-the-wrong-way/
Perhaps you meant to try:
c:\> bash -x script.sh foo ^"bar\^"baz^" bat
> Called from within Cygwin, the behavior is correct:
>
> $ bash -x script.sh foo bar\"baz bat
> + echo foo
> foo
> + echo 'bar"baz'
> bar"baz
> + echo bat
> bat
Moral of the story: POSIX rules are saner than cmd rules.
>
> Can you explain this difference? The reason I ask is that if this worked,
> the way Go constructs the command line string would be just fine.
If Go is not constructing the command line string in a manner that
matches that blog post, the bug would be in Go. Presumably, Cygwin is
correctly quoting things any time it calls into a non-Cygwin process
(but if not, give us a test case for us to patch cygwin, or even better
submit the patch).
--
Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3226
Virtualization: qemu.org | libvirt.org
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next prev parent reply other threads:[~2019-09-05 19:05 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-30 19:31 Stephen Provine via cygwin
2019-08-30 20:53 ` Brian Inglis
2019-08-30 21:21 ` Stephen Provine via cygwin
2019-08-31 4:18 ` Brian Inglis
2019-09-03 16:38 ` Stephen Provine via cygwin
2019-09-04 16:20 ` Brian Inglis
2019-09-04 23:46 ` Stephen Provine via cygwin
2019-09-05 5:29 ` Brian Inglis
2019-09-05 18:31 ` Stephen Provine via cygwin
2019-09-05 19:05 ` Eric Blake [this message]
2019-09-05 22:01 ` Stephen Provine via cygwin
2019-09-05 22:46 ` Eric Blake
2019-09-05 23:45 ` Stephen Provine via cygwin
2019-09-06 0:46 ` Steven Penny
2019-09-06 1:26 ` Eric Blake
2019-09-06 6:20 ` Stephen Provine via cygwin
2019-09-07 21:50 ` Brian Inglis
2019-09-07 12:05 ` Andrey Repin
2019-09-07 12:20 ` Andrey Repin
2019-09-09 16:47 ` Stephen Provine via cygwin
2019-09-09 16:57 ` Stephen Provine via cygwin
2019-09-09 17:11 ` Eric Blake
2019-09-09 19:05 ` Duncan Roe
2019-09-09 19:44 ` Andrey Repin
2019-09-10 12:43 ` Brian Inglis
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