Thanks for the answer, the question wasn't really leading anywhere other than idle curiosity. The answer seems like a good candidate for the FAQ.
jeb On 3/25/06, Eric Blake <[EMAIL PROTECTED]> wrote: > > Why can there be only 1 cygwin1.dll in the filesystem? Is this a > > limitation of the dll or is it just a problem with applications > > finding the wrong version of the cygwin1.dll when there are several? > > It is an intentional design decision of cygwin. In order to properly > emulate POSIX semantics in a relatively efficient manner, the .dll > opens a shared memory region when it is loaded. If there are > multiple versions of different copies of the .dll trying to play with > this shared memory region, you are practically guaranteed problems, > so the .dll detects if the magic number of the shared region matches > its expectations and forcefully exits before corrupting the other .dll's > memory. > > > Or is it just that certain cygwin registry keys get initialised wrong > > if its not installed correctly? > > The only use of the registry by cygwin is the mount table, and > even that might change in the future. Don't go blaming the > registry for this issue. > > > > > Does the cygwin1.dll have to be in /usr/bin or would it work in system32? > > Technically, as long as there is only one cygwin1.dll in the Windows > PATH (including the implicit search of the current directory before > %PATH%), it doesn't matter where it lives. But you are playing with fire > if you put it anywhere besides where setup.exe puts it, namely, /usr/bin. > You are free to remount /usr/bin to live in some other location, if that > helps, but this mailing list will NOT give any support for installations > that put cygwin1.dll in non-standard locations other than to say > delete your duplicate copies. We even have an acronym for it: > http://cygwin.com/acronyms/#3PP > > > > > I'm sure this must've been asked before but I couldn't find it in my > > search of the archives and users guide? > > This topic came up just last month, although you are right > that without knowing good search terms it might not be > the easiest to find (I did a google for > "site:cygwin.com mismatched dll"): > http://www.cygwin.com/ml/cygwin/2006-02/msg00085.html > > -- > Eric Blake > -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/
