I suspect you should be doing something like this:

Note: If you wish to await the Promise and discard its result, using 
try await $p.start;

[download]
will throw if the program exited with non-zero status, as the Proc returned as the result of the Promise throws when sunk and in this case it will get sunk outside the try.
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In reply to Re: Perl 6 Sending input to Proc::Async by BrowserUk
in thread Perl 6 Sending input to Proc::Async by ctilmes

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