Zombie or Defunct Process
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If a child proces tries to teminate,its association with parent remains until the parent terminates normally or calls wait.
- The child process entry in process table is therfore not freed up immediately.
- Althougth the process is no longer active, the child remains still in system because its exit code is needed to be stored in case of parent subsequently
calls wait.
- The process becomes defunct or zombie process.
- It is shown by ‘Z’ or ‘Z+’ in process table.
- If the parent is terminated abnormally, the zombie child process will not be terminated (which is not good).
