You can also use the LaunchCommand function in Bazaar/SysInfo package Smile
String LaunchCommand(const char *cmd)
where cmd is just the command line string. It returns the command output.
It is documented and if you see the code in the same SysInfo.cpp you will see many examples of its use.
This function does work for Windows and Linux. The exception is in basic OS commands in Windows like "dir" and "copy". If you want them to work out of a command line and hidden it will be needed something different.
It is not usually necessary as this commands are so basic that their functionality is included in libraries (list files in folder, copy files, ...).