System class/package?

We need a way to provide portable substitutions for commands like "rm -rf", "mkdir -p" and so on. So I'ld like to make a "System" class providing function for each command. In general we could take a UNIX command, make a function for it that takes two parameters: the regular list of arguments, and a list of options. For example: System::rm($this->tmpdir, "recursive") or with multiple params/options: System::cp(array("original.dat", "copy.dat"), array("preserve", "verbose")) Does anyone think it's ugly to put these functions straight into the "System" class? - Stig