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RE: Dynamic loading of cygwin dependent dlls


DOH!
> char *dlls[] = {
> 	"pseudostubs.dll",
> 	"foo.dll",
> 	"psuedostubs.dll",
> 	NULL
> };
should be
> char *dlls[] = {
> 	"psuedostubs.dll",
> 	"foo.dll",
> 	"psuedostubs.dll",
> 	NULL
> };

and all works

reid


> -----Original Message-----
> From: Reid Thompson 
> Sent: Tuesday, August 10, 2004 3:57 PM
> To: Reid Thompson; Peter Ekberg; cygwin@cygwin.com
> Subject: RE: Dynamic loading of cygwin dependent dlls
> 
> 
> actually -- that's not it, as this code, gives the following results:
> 
> CODE-----------CODE
> #include <stdio.h>
> #include <dlfcn.h>
> 
> char *dlls[] = {
> 	"pseudostubs.dll",
> 	"foo.dll",
> 	"psuedostubs.dll",
> 	NULL
> };
> 
> int main(void)
> { 
> 	int i;
> 	void *res;
> 	
> 	for(i=0; dlls[i]; ++i) {
> 		printf("%s\t", dlls[i]);
> 		res=dlopen(dlls[i], RTLD_LAZY | RTLD_GLOBAL);
> 		if(!res)
> 			printf("%s\n", dlerror());
> 		else
> 			printf("ok\n");
> 	}
> 
> 	return 0;
> }
> RESULTS-------------RESULTS
> pseudostubs.dll dlopen: Win32 error 126
> foo.dll ok
> psuedostubs.dll ok
> 
> reid
> 
> 
> > -----Original Message-----
> > From: Reid Thompson
> > Sent: Tuesday, August 10, 2004 3:49 PM
> > To: Peter Ekberg; cygwin@cygwin.com
> > Subject: RE: Dynamic loading of cygwin dependent dlls
> > 
> > 
> > take the underscore out of the dll name
> > 
> > psuedo_stub -> psuedostub
> > 
> > reid
> > 
> > 
> > > -----Original Message-----
> > > From: Peter Ekberg [mailto:peda@axentia.se]
> > > Sent: Tuesday, August 10, 2004 3:11 PM
> > > To: cygwin@cygwin.com
> > > Subject: Re: Dynamic loading of cygwin dependent dlls
> > > 
> > > 
> > > Christopher Faylor wrote:
> > > >On Thu, Aug 05, 2004 at 09:09:40AM +0200, Peter Ekberg wrote:
> > > >>I have read several messages stating that dlopen does 
> not work for
> > > dlls
> > > >>that depend on cygwin1.dll.
> > > >>(e.g. 
> http://sources.redhat.com/ml/cygwin/2004-06/msg01056.html).
> > > >>I have also understood that this is due to some structures
> > > not being
> > > >>initialized in that case.
> > > >>
> > > >>Is this dlopen problem limited to non-cygwin apps? I.e. 
> is it true 
> > > >>that an app that depends directly on the cygwin1.dll is
> > > incapable of
> > > >>dlopening dlls that depend on cygwin1.dll?
> > > >
> > > >No, it is not true.  dlopen would be pretty worthless if it
> > > didn't work
> > > >in a standard cygwin program.
> > > 
> > > Indeed. Knowing that it should work, I was inspired to do 
> some more 
> > > tests.
> > > 
> > > The reason I asked is that the following results in a dll 
> that can't 
> > > be
> > > dlopened:
> > > 
> > > foo.c:
> > > ------------8<---------------
> > > __declspec(dllexport) int foo(int bar);
> > > 
> > > int foo(int bar)
> > > {
> > > 	return bar;
> > > }
> > > ------------8<---------------
> > > 
> > > Build commands:
> > > $ gcc -c foo.c
> > > $ dlltool --dllname pseudo_stubs.dll --exclude-symbols 
> > > DllMain@12,_cygwin_dll_entry@12,_cygwin_noncygwin_dll_entry@12
> > ,DllMainCR
> > > TStartup@12,DllEntryPoint@12 --output-def foo.def  foo.o
> > > $ dllwrap --dllname pseudo_stubs.dll --output-lib 
> pseudo_stubs.dll.a 
> > > --def foo.def foo.o -L/usr/lib
> > > 
> > > However, further tests have shown that if I change the name 
> > > pseudo_stubs to foo in the above commands, it works like a charm. 
> > > Like this:
> > > 
> > > $ gcc -c foo.c
> > > $ dlltool --dllname foo.dll --exclude-symbols 
> > > DllMain@12,_cygwin_dll_entry@12,_cygwin_noncygwin_dll_entry@12
> > ,DllMainCR
> > > TStartup@12,DllEntryPoint@12 --output-def foo.def  foo.o
> > > $ dllwrap --dllname foo.dll --output-lib foo.dll.a --def foo.def 
> > > foo.o -L/usr/lib
> > > 
> > > I use this program to test whether the resulting dll works:
> > > 
> > > load.c
> > > ------------8<---------------
> > > #include <stdio.h>
> > > #include <dlfcn.h>
> > > 
> > > char *dlls[] = {
> > > 	"pseudo_stubs.dll",
> > > 	"foo.dll",
> > > 	NULL
> > > };
> > > 
> > > int main(void)
> > > { 
> > > 	int i;
> > > 	void *res;
> > > 	
> > > 	for(i=0; dlls[i]; ++i) {
> > > 		printf("%s\t", dlls[i]);
> > > 		res=dlopen(dlls[i], RTLD_LAZY | RTLD_GLOBAL);
> > > 		if(!res)
> > > 			printf("%s\n", dlerror());
> > > 		else
> > > 			printf("ok\n");
> > > 	}
> > > 
> > > 	return 0;
> > > }
> > > ------------8<---------------
> > > 
> > > I build load.c with "gcc load.c -o load" and ./load produces this
> > > output:
> > > pseudo_stubs.dll		dlopen: Win32 error 998
> > > foo.dll	ok
> > > 
> > > Any help on this would be appreciated.
> > > 
> > > Cheers,
> > > Peter Ekberg
> > > 
> > > 
> > 
> > --
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> > 
> 
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