Ansible: do something accordingly based on the output of shell commands ?

---
- hosts: localhost
gather_facts: no
tasks:
- name:  "echo pid"
shell: ls >/dev/null 2>&1 && echo $

register: stat_result


- debug: var=stat_result.stdout


- name: do someting else


action: shell ls -l

when: stat_result.stdout >1
register: pr
- debug:  var=pr.stdout

Registered variables have useful attributes like :
changed – set to boolean true if something happened (useful to tell when a task has done something on a remote machine).
stderr/stdout – contains stringy output from stderr/stdout.
stdout_lines – contains a list of lines.

外加一个例子：

---

 - hosts: localhost

   gather_facts: no

   tasks:

   - shell: echo ‘first;second;third’

     register: result

   # result.stdout.split(';')

   - debug: msg="insert into exp values ("{{result.stdout|replace(';', '","')}}");'"

这里用了split/replace。