[!exec:echo] skip
[!exec:false] skip

# TODO: the '\n' below doesn't work on Windows on Github Actions, which does
# have coreutils like "echo" installed. Perhaps they emit CRLF?
[windows] skip

exec echo foo
stdout foo

exec echo foo &
exec echo bar &
! exec false &

# Starting a background process should clear previous output.
! stdout foo

# Wait should set the output to the concatenated outputs of the background
# programs, in the order in which they were started.
wait
stdout 'foo\nbar'

exec echo bg1 &b1&
exec echo bg2 &b2&
exec echo bg3 &b3&
exec echo bg4 &b4&

wait b3
stdout bg3
wait b2
stdout bg2
wait
stdout 'bg1\nbg4'

# We should be able to start several background processes and wait for them
# individually.

# The end of the test should interrupt or kill any remaining background
# programs.
[!exec:sleep] skip
! exec sleep 86400 &