porting an xwin-linked library

[Michael Rogers <michael_lloyd_rogers at yahoo dot com>]

I'm learning this process as I go but it's frustrating and time-consuming.? I'm trying to compile an xwindows-based?graphing library from a unix tarball that didn't anticipate cygwin porting.? The configure script had sections for linux, solaris, aix and something?others,?but not cygwin.? This is my first attempt at?*any* cygwin?port. 
I actually got it to compile by overriding the archive name checks in the "configure" file with their asbolute path names - I pointed it to the import libraries libX11.dll.a, libXpm.dll.a, libtcl84.a and libtk84.a.? I ran the configure script and made makefiles which compiled the?entire distribution, including test files that linked to the libraries.? As?one might expect, it didn't run because I was cavalier about linking the libraries correctly.? I compiled it debuggable and got a segmentation fault?immediately.? I'm a newbie to gdb (I'm used to gui based debuggers)?so I haven't tracked down the?point that this happens yet, but I?did an "info sharedlibrary" (or something like that) and?it appears?that?the linker was smart enough that it had loaded?the?actual DLLs?that run under cygwin-x for the four archives listed above.? So I think the problem is that it made a static archive,?mylib.a, and the test programs tried to link to that.? I
 suppose that's a no-no under cygwin-x.
I sort of expected this but I don't know how to fix it.? I tried?recompiling the?library as a DLL?in?its?/src?directory on the command line but it's not working.? In what appears to be the?closest attempt?I've gotten so far - using "gcc -shared -o mylib.dll ./*.o -lX11 -lXpm -ltcl84 -ltk84" -?the linker?complains that the first object?it tries to?link has multiple definitions of all its functions.? I suppose there are?some?switches or variables?I could?define or modify?in the Makefiles or the configure file that would make sure that the whole thing automatically?compiled and linked?everything consistently for cygwin-x but I just don't know that stuff well enough at this point.?
It's ironically a pity that the configuration/make system worked so well with a little redirection to the import libraries because I don't know enough about how to modify it make dynamic link libraries, or ensure it's linking correctly to?DLLs,?if its?running under cygwin-x.? I still might also not be linking right to xwindows and tcl libraries but I *think* the linker did that right when I gave it the import lib files (eg, libX11.dll.a).? Is that all you need to do?
I wouldn't be averse to just recompiling?everything piecemeal,?from the comand line, but I've been reluctant so far because I don't know?what other cygwin specific libraries or other switches I'd need to include.? That's transparent running make. This?uses those big standardized GNU configure and Makefiles so its pretty opaque to a newbie.? I suppose I can?back that out?by?searching?on the arguments to the "CC" command in the Makefiles.
If anybody has some quick?insights?for me here I'd really appreciate it.? This is taking forever.




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