Hello all. I am porting GT.M (https://www.fisglobal.com/Solutions/Services/Database-Engine) to run on Cygwin x86. My changes are here: https://github.com/shabiel/fis-gtm/. GT.M is used in healthcare and banking; I happen to work in the former field.
The problem I am having is that GT.M opens libicuio via dlopen, and then loads the function pointers into a data structure via function name using dlsym. For the curious, the code is in gtm_icu_init() in gtc_icu.c I took me a while, but I eventually figured out that dlls that are opened via dlopen need to be in the PATH in Cygwin. I saw this in an earlier Cygwin mailing list message. However, no matter what I do, I can't seem to get a non-null reference to a named symbol in libicuio via dlsym. Here's what I tried: 0. nm shows the symbols in the file I want to open; strace shows me opening it (it's /usr/lib/cygicuio56.dll). 1. Compiled libicu from source with a flag for Cygwin: http://site.icu-project.org/ 2. Used underscores in front of the symbol 3. Tried creating an import library using the instructions at https://cygwin.com/cygwin-ug-net/dll.html#dll-build at the bottom and then add the archive to the gcc compile command as a source file. (These instructions need to be improved! I had no idea what to do with a .a file after I got it). Here's a test program that I have written. Note that dlsym returns the obscure error message "no such process", which doesn't make any sense to me, as I am not looking for a "process" but a symbol. sam@horus ~/fis-gtm-cygwin $ cat test.c #include <dlfcn.h> #include <stdio.h> #include <stdlib.h> int main (int arg, char **argv) { void *ptr = dlopen("cygicuio.dll", RTLD_LAZY); if (ptr != NULL) { printf("%p\n",ptr); } else { printf("%s",dlerror()); exit(1); } void *ptr2 = dlsym(ptr,"uset_open"); if (ptr2 != NULL) { printf("%p\n",ptr2); } else { printf("%s",dlerror()); exit(1); } return 0; } sam@horus ~/fis-gtm-cygwin $ gcc -Wall -otest.o test.c sam@horus ~/fis-gtm-cygwin $ ./test.o No such file or directory sam@horus ~/fis-gtm-cygwin $ PATH=/usr/lib:/usr/bin:/usr/local/bin:. ./test.o 0x6aa40000 No such process sam@horus ~/fis-gtm-cygwin -- Sam Habiel, Pharm.D. VISTA Expertise Network -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
