How to run a script and not wait for it in Perl?

Question

I have a system call in Perl that looks like this:

system('/path/to/utility >> /redirect/to/log file');

But this waits for utility to complete. I just want to trigger this and let the Perl script finish irrespective of whether the utility call finished or not.

How can I do this?

I tried changing the line to

system('/path/to/utility >> /redirect/to/log file &');

but this syntax still waits for the call to finish on Windows. I need to make it work on Linux as well as Windows.

Answer 1

if ($^O eq 'MSWin32') {
   system('start "" \\path\\to\\utility >> \\redirect\\to\\log_file');
} else {
   system('/path/to/utility >> /redirect/to/log_file &');
}

or

if ($^O eq 'MSWin32') {
   system(1, '\\path\\to\\utility >> \\redirect\\to\\log_file');
} else {
   system('/path/to/utility >> /redirect/to/log_file &');
}

Answer 2

You could try looking at the fork keyword, and launch your system command from the forked process. See the perlipc manpage for examples.