The return value is the exit status of the program
             as returned by the "wait" call.  To get the actual
             exit value shift right by eight (see below).  See
             also "exec".  This is not what you want to use to
             capture the output from a command, for that you
             should use merely backticks or "qx//", as described
             in "`STRING`" in perlop.  Return value of -1
             indicates a failure to start the program (inspect $!
             for the reason).

             Like "exec", "system" allows you to lie to a program
             about its name if you use the "system PROGRAM LIST"
             syntax.  Again, see "exec".

             Because "system" and backticks block "SIGINT" and
             "SIGQUIT", killing the program they're running
             doesn't actually interrupt your program.

                 @args = ("command", "arg1", "arg2");
                 system(@args) == 0
                      or die "system @args failed: $?"

             You can check all the failure possibilities by
             inspecting $? like this:

                 $exit_value  = $? >> 8;
                 $signal_num  = $? & 127;
                 $dumped_core = $? & 128;

             or more portably by using the W*() calls of the
             POSIX extension; see perlport for more information.