I just learned that under IRIX, neither glXGetProcAddress, glXGetProcAddressARB nor glXGetProcAddressEXT is supported.

What is the standard procedure for fetching OpenGL extension function pointers under IRIX?

Is it with dlopen/dlsym? Is it safe, and can you be sure which libGL.so you should load (e.g. /usr/lib/libGL.so)?