This involves the Dislin library I mentioned in an earlier mail. I used it earlier in Dev-C++ using Mingw. In that case case, I simply added the file 'dismgc.a' in the Linker parameters window. I want to test it in Linux now. And in the Linux version of the library, there are two files, 'dislin-9.0.a' and 'dislin-9.0.so' - which library file am I supposed to link to? And how do link to a single file, from the command line? Both the library files, the header file and the source file are in the same directory. I'm using Ubuntu 5.10, it has GCC 4.0.2. -- Rohit V. Bhute http://rvbhute.blogspot.com/