On Fri, Nov 13, 2015 at 8:45 AM, Linda Walsh <b...@tlinx.org> wrote:
>
> I'd like to be able to record stdout and stderr
> without using any temp files into bash array files, AND
> record the status of the command executed.
>
You can use coproc processes that would act as buffers.
Obvious Note: Avoid it if you're conservative about some undocumented
areas that would look too hacky to you.
Concept:
#!/bin/bash
function sponge {
while read -r __ && [[ $__ != __EOF__ ]]; do ## Or use a
keyword that's more unusual. Closing one end of the input pipe seems
unreliable. I also tried using traps for flushing output; didn't work
so well. (But you can try those ideas. I haven't tested how adding
`sleep` affects them.)
LINES+=("$__")
done
printf '%s\n' "${LINES[@]}"
exec sleep 1
}
function run_with_captured_output {
local C0 C1 P0 P1 R __
exec 4>&2 2>/dev/null ## Avoid warning.
coproc C0 (sponge)
P0=$!
coproc C1 (sponge)
P1=$!
exec 2>&- 2>&4 4>&-
disown "$P0" "$P1" ## This may be needed or not.
"$@" >&"${C0[1]}" 2>&"${C1[1]}"
R=$?
__A0=() __A1=()
echo __EOF__ >&"${C0[1]}"
while read -u "${C0[0]}" -t 0.1 __; do
__A0+=("$__")
done
echo __EOF__ >&"${C1[1]}"
while read -u "${C1[0]}" -t 0.1 __; do
__A1+=("$__")
done
# TODO: Not sure how a proper coproc cleanup is done. Closing
FDs does funny things. Perhaps it's automatic, but not sure how
disown affects it. We could examine the source code but not sure if
that would be reliable enough for all versions of bash including the
upcoming ones.
return "$R"
}
function create_random_output {
local I
for (( I = 0; I < 5; ++I )); do
echo "OUT: $RANDOM"
echo "ERR: $RANDOM" >&2
done
}
run_with_captured_output create_random_output
echo "Returned status: $?"
printf 'Stdout: %s\n' "${__A0[@]}"
printf 'Stderr: %s\n' "${__A1[@]}"
Output:
Returned status: 0
Stdout: OUT: 26079
Stdout: OUT: 21138
Stdout: OUT: 17971
Stdout: OUT: 8460
Stdout: OUT: 7185
Stderr: ERR: 19874
Stderr: ERR: 4559
Stderr: ERR: 18830
Stderr: ERR: 19818
Stderr: ERR: 21562
