# kill4-p.sh: test of the kill built-in for any POSIX-compliant shell, part 4

posix="true"

# This FIFO is for synchronization between processes. First, it ensures the
# receiver has started before the sender sends a signal. Next, the receiver
# tries to reopen the FIFO so that the receiver does not exit before it
# receives the signal.
mkfifo fifo

# all processes in the same process group
test_oE 'sending signal to process 0' -m
kill -s HUP 0 >fifo | cat fifo fifo
kill -l $?
__IN__
HUP
__OUT__

test_oE 'sending signal with negative process number: -s HUP' -m
(
pgid="$(exec sh -c 'echo $PPID')"
kill -s HUP -- -$pgid >fifo | cat fifo fifo
)
kill -l $?
__IN__
HUP
__OUT__

test_oE 'sending signal with negative process number: -1' -m
(
pgid="$(exec sh -c 'echo $PPID')"
kill -1 -- -$pgid >fifo | cat fifo fifo
)
kill -l $?
__IN__
HUP
__OUT__

(
setup 'halt() while kill -s CONT $$; do sleep 1; done'
mkfifo fifo1 fifo2 fifo3

test_oE 'sending signal to background job' -m
# The subshells stop at the redirections, waiting for the unopened FIFOs.
(>fifo1; echo not reached 1 >&2) |
(>fifo2; echo not reached 2 >&2) |
(>fifo3; echo not reached 3 >&2) &
halt &
kill -s USR1 '%?echo'
wait '%?echo'
kill -l $?
kill -s USR2 %halt
wait %halt
kill -l $?
__IN__
USR1
USR2
__OUT__

test_oE 'sending to multiple processes' -m
# The subshells stop at the redirections, waiting for the unopened FIFOs.
(>fifo1; echo not reached 1 >&2) &
(>fifo2; echo not reached 2 >&2) &
kill '%?fifo1' '%?fifo2'
wait '%?fifo1'
kill -l $?
wait '%?fifo2'
kill -l $?
__IN__
TERM
TERM
__OUT__

)