Hi Gurus, Sorry to sound ignorant, but after 38 years of coding, little problems still bug me, as I am a beginner with Linux. I am running SuSE 9.1 Q1 When I try to compile and link a program the system says that the XWindow functions are not defined. That is, not found in the libraries. But I cannot find any documentation (in the masses of it) which tell me how to link. (I can manage the MS Windows API, but not the Linux.) Q2 I am running 64 bit Linux, but there appears to be no documentation about the arguments expected by SuSE XWindow. That is: are the normal 32 bit integers still 32 bit or change to 64 bit for function calls? More importantly, where is the documentation? Any help would be appreciated, especially a pointers into the documentation. I have a stack of books on Linux, and there is a million lines of information with which I am familiar with after 38 years of coding, but I cannot find the 'new' stuff required to transfer standard 32 bit Linux to 64 bit Linux, and I cannot find stuff which explains libraries. Kind regards, Colin Carter (colincarter@onetel.net.uk)