modify mount options

example_options.txt

# /tmp/example_otpions.txt
rw,noatime,data=ordered,acl

output

PLAY [localhost] **************************************************************

GATHERING FACTS ***************************************************************
ok: [localhost]

TASK: [get root mount options] ************************************************
changed: [localhost]

TASK: [do something funky] ****************************************************
changed: [localhost]

PLAY RECAP ********************************************************************
localhost                  : ok=3    changed=2    unreachable=0    failed=0

tmp.yml

---
- hosts: localhost
  tasks:
    - name: get root mount options
      shell: cat /etc/mtab | grep ' / ' | grep -v 'rootfs' | awk '{print $4}'
      register: value

    - name: do something funky
      shell: echo "{{ value.stdout + ',acl' }}" >> /tmp/example_options.txt