[CMake] EXECUTE_PROCESS too good at running programs

[Brad King]

Brandon J. Van Every wrote:
> Brad King wrote:
>> Brandon J. Van Every wrote:
>>   
>>> I explained the situation pretty clearly, I thought. 
>>> E:\msys\1.0\bin\makefile does *NOT* run under a Windows command prompt. 
>>> It's not supposed to.  As I said before, there's a comment at the top of
>>> the binary that says it's not supposed to.  Just to reiterate again in
>>> case there's any doubt:
>>>
>>> E:\msys\1.0\bin>dir makeinfo
>>> Volume in drive E is MONDRIAN
>>> Volume Serial Number is 9CA0-CADF
>>>
>>> Directory of E:\msys\1.0\bin
>>>
>>> 04/30/2004  11:15p             180,224 makeinfo
>>>               1 File(s)        180,224 bytes
>>>               0 Dir(s)  11,499,749,376 bytes free
>>>
>>> E:\msys\1.0\bin>cmd
>>> Microsoft Windows 2000 [Version 5.00.2195]
>>> (C) Copyright 1985-2000 Microsoft Corp.
>>>
>>> E:\msys\1.0\bin>makeinfo
>>> 'makeinfo' is not recognized as an internal or external command,
>>> operable program or batch file.
>>>     
>>
>> I don't think your test is reliable.  My MSYS has a makeinfo.exe and it
>> runs under a windows shell.
>>   
> 
> My test is plenty reliable.  I have ***makeinfo***, not makeinfo.exe. 
> Please read *ALL* the details of my post.  There are ~30 tools in
> E:\msys\1.0\bin that do not have .exe suffixes, run fine under a MSYS
> shell, and are not intended to be run under anything but a MSYS shell. 
> EXECUTE_PROCESS is finding a way to run them.  My wild-assed-guess as to
> explanation, is that it execs arbitrarily named files, and does not
> check whether the filename is valid for a Windows command prompt.  These
> MSYS tools are probably valid apps in some Windows-native sense, but not
> to a Windows command prompt.

I did read your entire post.  I'm saying that on my system makeinfo will
run under VS.  Your test is not reliable because it does not try running
it under the build environment.

> That is a (tedious) workaround, but I still say the behavior of
> EXECUTE_PROCESS is bugged.  I don't think anyone should have to write an
> OS-specific C coded exec wrapper just to determine if "makeinfo"
> actually works under the build environment.

There is absolutely no way EXECUTE_PROCESS can know exactly how the
build environment will run a tool.  This is the purpose of try-compiles.
  You don't need to write any C code, just a small CMakeLists.txt file
that has a custom target to try running makeinfo.  It is not a
work-around, but the right way to do it.

-Brad