Test the basic knowledge of FreeBSD.
- What’s in the file /etc/ttys? - Configuration for virtual consoles for the startup. By default FreeBSD has 8 virtual consoles.
- You’re told that the permissions of a file are 645. Quick, how do you calculate what it means? - The permissions value are always 4 for read, 2 for write, 1 for execute. The three numbers are always for owner, group, and everybody on the system. Therefore 645 means: owner - read and write, group - read only, everybody - read and execute. You’ll rarely see such a permission set, but for interview question it might just work.
- Explain what each column means in the top command:
48630 techinterviews 2 0 29816K 9148K select 3:18 0.00% 0.00% navigator-linu 175 root 2 0 924K 252K select 1:41 0.00% 0.00% syslogd 7059 techinterviews 2 0 7260K 4644K poll 1:38 0.00% 0.00% mutt
The first column is the process id, followed by the username, followed by priority…
- Explain the difference between SIGTERM and SIGKILL. SIGTERM asks the application to terminate in a polite way, it warns about the pending closure and asks the app to finish whatever it is doing. SIGKILL will kill the process no matter what. This is telling the application that it will be shut down no matter what.
- Explain the difference between SIGHUP, SIGUSR1 and SIGUSR2. Those are application specific and therefore are not defined on the OS level.
- How do you change your shell to bash?
% chsh -s /usr/local/bin/bash