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.
Check the perlfunc man page for more details. The perlfunc man page can be accessed by setting the MANPATH to include the "<perl_install_dir>/man" directory.