Update faq.rst

[tdram]

Using backup_file gives error as the name is now changed to backup in newer Ansible versions.

Please update.

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[samccann]

@mattclay - did backup_file change? I still see it here

[mattclay]

@samccann No, it hasn't changed. I just tested the devel branch and the result still contains backup_file.

[tdram]

I still see it as backup

ansible --version ansible [core 2.17.9]

TASK [update : Debug] *************************************************************************************************************************************************** ok: [10.100.12.2] => { "updated": { "ansible_facts": { "discovered_interpreter_python": "/usr/bin/python3.11" }, "backup": "/home/raw/file.txt.3876448.2025-03-22@07:58:37~", "changed": true, "diff": [

[mattclay]

@tdram Can you provide a complete reproducer for what you're seeing?

[tdram]

Hi,

Please find:

1. Playbook

  hosts: local
  remote_user: root
  tasks:
    - name: Add this line in the file
      ansible.builtin.lineinfile:
        backup: true
        path: /root/docs/file.txt
        line: "Hello"
      register: output
    - name: Debug
      ansible.builtin.debug:
        var: output

Output:

TASK [Gathering Facts] ******************************************************************************************************************************************************
ok: [10.100.12.2]

TASK [Add this line in the file] ********************************************************************************************************************************************
changed: [10.100.12.2]

TASK [Debug] ****************************************************************************************************************************************************************
ok: [10.100.12.2] => {
    "output": {
        "backup": "/root/docs/file.txt.3910784.2025-03-24@22:15:48~",
        "changed": true,
        "diff": [
            {
                "after": "",
                "after_header": "/root/docs/file.txt (content)",
                "before": "",
                "before_header": "/root/docs/file.txt (content)"
            },
            {
                "after_header": "/root/docs/file.txt (file attributes)",
                "before_header": "/root/docs/file.txt (file attributes)"
            }
        ],
        "failed": false,
        "msg": "line added"
    }
}

PLAY RECAP ******************************************************************************************************************************************************************
10.100.12.2            : ok=3    changed=1    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0 

When I tried to implement this with block and rescue, I used {{ updated['backup_file'] }}" as documented from here and it said backup_file is not defined and hence I debugged and used backup option instead of backup_file and it worked.

[mattclay]

@tdram The example being updated in this PR is for the template module, not the lineinfile module. They have different return values.