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From: David Abrahams <dave AT boost-consulting DOT com>
Subject:  Re: very odd behavior of Cygwin python from CMD
Date:  Sat, 03 Mar 2007 23:42:12 -0500
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Brian Dessent <brian AT dessent DOT net> writes:

> David Abrahams wrote:
>
>> Now, I am writing a program that must use CMD to probe for python in
>> the PATH and check its version.  If I do the naive thing and just try
>> to invoke "python," and there's a Cygwin installation, my program will
>> crash or freeze.  So the question is, what do I do instead?
>
> One way to handle this would be to check if the thing found in the path
> looks like a symlink (say, by having a size less than a hundred bytes
> and the 'S' attribute set) 

Ouch.  From the looks of it, even some symlinks to executables
(e.g. python) get an .exe extension, so unless anyone else has bright
ideas, that's what I'll /have/ to do.  What a hack (no offense
intended).

> and if so, launch it as "sh.exe -c python", using sh.exe in the same
> dir as the shortcut.  This will invoke python through the shell,
> which will follow symlinks.

Ja; except that that begs the question -- sh.exe could be a symlink,
as it often is to bash.  In fact it isn't even important for me to
invoke python in that case; I just need to detect it and avoid it.

> Non-cygwin programs will have no idea what a symlink is.

Right.

Thanks,

-- 
Dave Abrahams
Boost Consulting
www.boost-consulting.com


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