system function — Runs a program
int system(const char* command)
The system
function passes
command
to the host operating
system to run as an external command. The use and interpretation of
the command string is implementation-defined.
The return value is implementation-defined.
If command
is null, the
return value is true (nonzero) if a command processor is available;
it is false (0
) if no command
processor is available.