Pure C89 source for a small CPU activity monitoring library for Linux (and probably other UNICES like *BSD with a /proc filesystem). Exposes CPU usage since the last call to CpuMon_getUsage and separates (niced) userland, kernel, idle and I/O-wait time spent; in percentages multiplied by 1000. Uses integer arithmetic only - no floating point. Includes example usage giving CPU info each second.