From @zoffixznet

zoffix@​VirtualBox​:~$ cat ~/bin/streams.p6
#!/usr/bin/env perl6

my $p = Proc​::Async.new​: 'perl6', '-e', 'exit 255';
try await $p.start;
say 'still here';

zoffix@​VirtualBox​:~$ streams.p6
The spawned process exited unsuccessfully (exit code​: 255)
  in block <unit> at /home/zoffix/bin/streams.p6 line 4

zoffix@​VirtualBox​:~$

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ZZ | https://twitter.com/zoffix

From @zoffixznet

A bit of conversation on the topic here​: http://irclog.perlgeek.de/perl6/2016-07-20#i_12870811

From @zoffixznet

Not a bug after all​: the result of the returned promise is a Proc which passes the try check but then gets sunk and a Proc.sink() throws if the process run is unsuccessful.

@zoffixznet - Status changed from 'new' to 'rejected'