If you just want to execute a program rather then a shell command, then you can use the multiple argument form of either, and you won't have to worry about escaping.

system('cat foo bar');     # Cats 'foo' and 'bar'
system('cat', 'foo bar');  # Cats 'foo bar'

system('some command');                     # Executes 'some'
system({ 'some command' } 'some command');  # Executes 'some command'
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Some escapes aren't possible in Windows, so avoid " and control characters.