BASH script: Trying to get 3 return codes/exit status to give me a "global exit"

Question

I've got a working global_exit i copied from somewhere, it's for two command exits. Renaming 'echo' to 'ech' to force a failure allows me to test all the permutations work - and they do here:

echo "$USER $(date +%F)" |& tee info.log
info_exit=${PIPESTATUS[0]}
echo "$USER $(date +%F)" |& tee list.log
list_exit=${PIPESTATUS[0]}

global_exit=$(( info_exit > list_exit ? info_exit : list_exit ))

if [ ${global_exit} = "0" ]; then
echo ">> SUCCESS <<"
elif [ ${global_exit} = "1" ]; then
echo ">> WARNINGS <<"
else
echo ">> FAILED <<"
fi
exit

How can i expand that to three RCs? I haven't been able to find the rules around how to use this feature. I just guessed using the below, but it doesn't work across all permutations of the same test (one-by-one rename just one echo to ech to force a failure):

echo "$USER $(date +%F)" |& tee info.log
info_exit=${PIPESTATUS[0]}
echo "$USER $(date +%F)" |& tee list.log
list_exit=${PIPESTATUS[0]}
echo "$USER $(date +%F)" |& tee check.log
check_exit=${PIPESTATUS[0]}

global_exit=$((( info_exit > list_exit > check_exit ? info_exit : list_exit > check_exit )))

if [ ${global_exit} = "0" ]; then
echo ">> SUCCESS <<"
elif [ ${global_exit} = "1" ]; then
echo ">> WARNINGS <<"
else
echo ">> FAILED <<"
fi
exit

Thanks :)

Answer 1

If I have the intent correct and you wish to continue with the code as written, change this:

global_exit=$((( info_exit > list_exit > check_exit ? info_exit : list_exit > check_exit )))

to this:

global_exit=$((( info_exit > list_exit > check_exit ? info_exit : list_exit > check_exit ? list_exit : check_exit )))

As you have it, if info_exit is largest it works fine. If not, it sets global_exit to a 0 or 1 depending on whether list_exit > check_exit or not. With the additional condition added it will be set to the greater of list_exit or check_exit.

Answer 2

One possibility to check multiple return codes together for 0, 1 and all the rest is to combine the return codes:

echo "$USER $(date +%F)" |& tee info.log
exit_code=$((exit_code | PIPESTATUS[0]))
echo "$USER $(date +%F)" |& tee list.log
exit_code=$((exit_code | PIPESTATUS[0]))
echo "$USER $(date +%F)" |& tee check.log
exit_code=$((exit_code | PIPESTATUS[0]))

if (( 0 == exit_code )); then
  echo ">> SUCCESS <<"
elif (( 1 == exit_code )); then
  echo ">> WARNING <<"
else
  echo ">> FAILED <<"
fi

With this approach you can't distinguish between the exit codes and potentionally multiple return codes may occur but for a general OK / not OK return code it should be enough.

Answer 3

You could use a function and check all status codes of PIPESTATUS and save the highest value.

#!/bin/bash

max_exit=0

set_max_exit() {
  for i in "${PIPESTATUS[@]}"; do
    [ "$i" -gt "$max_exit" ] && max_exit=$i
  done
}

echo | grep x   # exit 1
set_max_exit

ech             # exit 127
set_max_exit

ls adfds        # exit 2
set_max_exit

if [ "$max_exit" -eq 0 ]; then
  echo ">> SUCCESS <<"
elif [ "$max_exit" -eq 1 ]; then
  echo ">> WARNING <<" >&2
else
  echo ">> FAILED <<" >&2
fi

exit "$max_exit"

Output:

$ ./script.sh
./script.sh: line 14: ech: command not found
ls: cannot access 'adfds': No such file or directory
>> FAILED <<
$ echo $?
127