Arguments parsing in cygwin executables

Sasha Unknown sasha2048+cygwin@gmail.com
Wed Jun 17 18:50:00 GMT 2015


Hello.

[Sorry if duplicate, previous message was sent from wrong address, so
not sure if it reached.]

==Preamble==
Some time ago I noticed that cygwin executables (e.g. bash, tar, echo
& so on) handle specially *, {} and some other symbols in
command-line, even when being invoked not from shell (e.g.
programmatic invocation or cmd.exe). After some googling, I found
CYGWIN=noglob setting, which fixed the issue. After enabling it I
hoped that cygwin executables will start parsing command-line in a
standard for Windows executables way (I am not talking about path
translation, only about handling special characters and splitting
command string into argv array).

==Main==
It revealed that even with CYGWIN=noglob, cygwin executables parse
command line differently from other windows executables. (Again, I
underline: I'm talking about invocation from cmd.exe or programmatic
invocation, not invocation from bash.) Concretely, the 3rd and 4th
test-cases from here fail:
https://msdn.microsoft.com/en-us/library/windows/desktop/17w5ykft(v=vs.85).aspx.
(BTW, ironically, with CYGWIN=glob only 3rd test-case fails.)

==Questions==
So, questions are:
1. Is this behavior intentional, or is it bug?
1a. If intentional: Maybe there is a way to force cygwin executables
to perform command-line parsing in windows-canonical way (i.e.
CommandLineToArgv-like)? (I am talking about splitting command string
into argv array, not about path translation.)
2. In any case, could you point me to part of cygwin sources which is
responsible for this? (In case of intentionality -- to understand what
behavior I'm now forced to adopt to, in case of bug -- to possibly aid
fixing.)

==Test cases==
1. I compiled code from the link above with g++.
2. And written simple simple script in bash:
> #!/bin/bash
> for a in "$@"; do echo "$((++i)): $a"; done
(to be called like this: c:\cygwin\bin\bash.exe c:\script.sh args-to-test)
Both have same behavior, which differs from canonical windows parsing.

==Additional==
What I'm trying to do?
I am trying to find proper way of passing parameters to cygwin
executables from non-cygwin application (which doesn't even know that
it's dealing with cywgin).
I suppose that if one wants *nix-typical parsing, he will use some
shell (e.g. bash), or at least CYGWIN=glob.

BTW, in CYGWIN=glob mode, curly braces are handled wrongly
(c:\cygwin\echo.exe {aa} should return {aa}, not aa; because no , or
.. inside {}).

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