I would like to ask a couple more questions please. I undestand the libusb nuance and was able to go from usb.h to libusb.a relatively easily. However, when I try what should be a simpler case, that of string.h, I cannot find a string.o in libc.so. I think this is a whole in my education more then anything else. I would appreciate a bit more tutelage on going from an arbitrary include file in /usr/include and figuring out how to then find the shared object library that includes the executable for a particular header include file. Thanks to Devon, I think I get the recipe to go from a shared object and figure out the source rpm, but I am missing the step before this. With Respect, Charles Krinke