in reply to Re^2: start up process without waiting
in thread start up process without waiting

Also, as you are tossing away your return values, you should not be using backticks. Not only is your intent misleading, using system also buys you automatic escaping if you use the multiple argument form:

for $file (@files) { system 'start', '/B', '/I', '', $file }

#11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.