PPID=? What mean?

[Fernando Boza]

I have the following output:

hp-act>#ps -u sybase | grep tail
28234 ? 0:00 tail
27135 ? 0:00 tail
28442 ? 0:00 tail
17366 ? 10:43 tail
28523 ? 0:00 tail
17881 ? 0:00 tail
27388 ? 0:03 tail
28348 ? 0:00 tail
25981 ? 0:04 tail
5031 ? 0:00 tail
24086 ? 0:00 tail
28543 ? 0:00 tail
28455 ? 0:00 tail
28449 ? 0:00 tail
27131 ? 0:03 tail


What mean?

[Don Morris_1]

If you lose the grep and pipe through more, etc. --- you'd see that the second column here is TTY, not PPID. So these are processes that have no controlling terminal.

Perhaps you want to use `ps -f -u sybase |grep tail` or some other combination which shows the PPID column?

[Steven E. Protter]

Shalom,

To answer the subject question. PPID is Parent Process ID, the Process ID that started the process listed.

SEP

[Vishu · Accepted solution]

Hi Fernando,

PPID is Parent Process ID. It is the process id from which the current process generates. Whenever a process points to a PPID, it means it is the child process of that parent process.

and ? in your case is TTY. It comes when your process does not have any controlling terminal.

Please use 'ps -ef -u sybase | grep tail' to get the PPID of the process.