Running shell script with "check program" results in zombie child

Hi,

Many cases, when we tried to implement our own checks as simple shell scripts monit has ended up creating defunct child zombies when running our checks. For example I have a script that checks if a directory does not contain any regular files:

#!/bin/bash

# Checks if a directory does not contain regular files

if [[ ! -d $1 ]]; then
  echo "Invalid usage"
  exit 100
fi

(( $(find $1 -type f | wc -l) == 0 ))

So this shell scripted is invoked from monit like this:

...
check program "monit-include-files-exist-copera" with path "/bin/bash -c '! /etc/scripts/directory_is_empty.sh some_dir'"
  every 5 cycles
  if status != 0 then alert
...

Then ps aux | grep defunc shows:

root     23223  0.0  0.0      0     0 ?        Zs   15:06   0:00 [bash] <defunct>
root     23930  0.0  0.0      0     0 ?        Zs   15:10   0:00 [bash] <defunct>
root     23932  0.0  0.0      0     0 ?        Zs   15:10   0:00 [monit_check_pro] <defunct>
root     23934  0.0  0.0      0     0 ?        Zs   15:10   0:00 [bash] <defunct>
root     23938  0.0  0.0      0     0 ?        Zs   15:10   0:00 [monit_check_pro] <defunct>
root     23946  0.0  0.0      0     0 ?        Zs   15:10   0:00 [monit_check_pro] <defunct>
root     23951  0.0  0.0      0     0 ?        Zs   15:10   0:00 [bash] <defunct>
root     23958  0.0  0.0      0     0 ?        Zs   15:10   0:00 [monit_check_pro] <defunct>
root     23968  0.0  0.0      0     0 ?        Zs   15:10   0:00 [bash] <defunct>
root     23974  0.0  0.0      0     0 ?        Zs   15:10   0:00 [monit_check_pro] <defunct>
root     24015  0.0  0.1   6388   684 pts/0    S+   15:11   0:00 grep defunc

It is pretty similar with some of our other shell scripts.

Any ideas?

Thanks a lot.

Cheers, Gyuri

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