UNIX for Advanced & Expert Users

I have an unix id (AIX system) which is used to run a couple of processes. They also write some log files into a file system (that is not in the home directory of the user id, but in different location).

One bad day, the id was deleted accidentally. But the home directory, files and everything else were safe.

The processes were running for long time, say days or weeks. I did not see they were stopped or affected directly due to the id deletion. However, the application that uses the processes was not behaving the way it had to.

My questions are:

1. How long the processes will go, after the id got delted?
2. What happens if one of the processes is trying to write the log throug the delted user id?
3. Any other hints or notes that will help me in this situation?

This is not a big deal to a running process unless it is coded to check for it and take some action. If larry was uid 1234, but you deleted larry from the system leaving some files existing and a process running, then ls and ps can only display the numeric uid as the owner, but other than that there is no problem. The kernel does not check /etc/passwd over and over again to allow a process to run. In fact it never checks /etc/passwd. Suppose that uid 5678 has never been assigned. A root process could still switch to uid 5678 and run normally. This uid 5678 process could create files in a world writable directory or a directory writable by its group. Files owned by uid not in the passwd file are common in an NFS environment.

Modern versions of cron are usually coded to check that an account is valid prior to starting a cron job. So if larry had any cronjobs or atjobs they probably would stop running.