In order to compile and install the CmdLine library on your system, type the following in the base directory of the CmdLine distribution:
> ./configure > make
Then copy cmdline.h and the library file (usually libcmdl.a found in the subdirectory cmdl) somewhere, where compiler and linker can find them. Since CmdLine uses autoconf you should have no trouble compiling it. Should you run into problems please report them to the the author.