UNIX for Dummies Questions & Answers

Hi,

We've a process on AIX UNIX server which is executed by multiple uses during a day. I wish to create a log file for every time the process is executed. I wish to know how unique are PID(s) on AIX UNIX servers if I were to name the log files with <date> and <PID>?

E.g. If I create my output files having the details such as

Code:

`date +%Y%m%d`_${$}_out.csv

With my limited understanding of UNIX and from what I've read on the forum https://www.unix.com/unix-advanced-expert-users/2896-obtaining-process-id-pid.html AIX system sequentially assigns a limited set of PIDs and re-utilizes them as and when processes get freed and slot is available for allocation by dispatcher.

Please suggest a suitable way to uniquely identify the process execution during the day. I am also considering adding datetime hh:mm:ss to the log name to uniquely identify the same E.g. change log file name to

Code:

 `date +%Y%m%d_%H%M%S`_${$}_out.csv

Thanks,

Yes, as you concluded, a pid is NOT unique within a 24 hour period. My understanding is they reach a maximum value, go back to lowest open value, and then start increasing again, reusing open slots are available.

Yes, the addition of "date +%Y%m%d_%H%M%S" to the file name will make the file name unique. That seems like a very good way, probably the best way.