RFC: Cygwin 64 bit?

[Daniel Colascione]

On 7/7/2011 7:26 PM, Yaakov (Cygwin/X) wrote:
>> The path from which the application started is always first.  The
>> current working directory is always prior to the paths from $PATH.
>> Whatever you do, if you're in the wrong dir it goes boom.
>
> So if the DLLs were in /usr/lib{,64}, and we started a 64-bit program
> with CWD of /usr/lib, then it goes boom.  Under what circumstances would
> CWD be /usr/lib* that this would be a concern in the first place?

Why _shouldn't_ CWD be /usr/lib? What if I want to look for a symbol in 
some library? What if I'm doing system maintenance? What if I'm just 
looking around? Why should ls(1) go boom if I run it in /usr/lib?  Using 
PATH adds quite a few failure modes, and I'm still having a hard time 
seeing the purported benefits over the separate-prefix approach.

>>> I'm dreaming here trying to get past
>>> this issue for cyg128.  If every use of a library were RUN TIME instead
>>> of LOAD TIME then you can segregate easier the library bitness into
>>> differing directories such as lib64.
>>
>> I still don't see the problem t use a cyg64 prefix.  It fixes almost
>> all problems, and the potential problems with dynamic loading can be
>> handled within dlopen.
>
> Wouldn't changing dlopen() to compute absolute paths for LoadLibrary()
> be easier (and perhaps safer) than changing the former to manipulate
> various permutations of DLL names?

All other things being equal, sure. But because separate prefix is 
necessary anyway, the permutation approach might as well be used.