686: Admin Mourning

Admin Mourning

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Title text: And every day it gets harder to fight the urge to su to the user and freak people out.

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Explanation

This explanation was found to be incomplete after being nominated for This Week's Explanation for Improvement. Although it was not featured, the nomination process revealed issues that still need to be addressed to meet our quality standards. Before removing this notice, read the August 2026 nomination and the comic discussion to ensure the issues raised by the Explanation Improvement Project have been satisfactorily addressed:   The second and third paragraphs of the explanation are too technical and should use simpler terms.   Explain what the HUP (Hang-up) signal is and what "detach and reattach that output" means.   The fourth panel assumes the user knows what a "command line interface" is. Explain that concept.   The journey from "Ghost in the Shell" to "Descartes' theory of mind-body dualism" can be explained better. You can help by editing the explanation! If you are new to wiki editing, see our editing FAQ for guidance.

The background images show the output from the ps command of Unix-like computer systems, which lists all running processes, including all interactive users logged in to the server. If a user did not log out, their processes would continue to run until stopped by a reboot. If some specific user died while logged in, the running sessions would still appear in the ps output and could remind other users of them.

When a session is closed, its descendent processes are sent the HUP (Hang-up) signal — a signal sent to a process when its terminal or connection is disconnected, which normally causes them to terminate. However, the popular utility screen enables a user to detach the output from the session and reattach that output later, thus surviving between sessions.

A system administrator (sysadmin or admin) is a person who maintains a computer system, such as a server used by multiple users. An admin is typically a superuser, which has higher privileges than the common user. Superusers are called "root" in most Unix systems.

This comic depicts an admin at a dilemma. The admin is hesitant to reboot a server that still has active processes from a deceased user named "sam", as the admin is afraid it might erase the last artifact of the user. However, it is a good habit for an admin to reboot a server, as it can help update software and cleanse possible memory leaks or corruption, which can mitigate security issues.

The prose is ended with a pun on the expression, "Ghost in the Shell", which is the title of a popular manga series. It originally derives from the expression "ghost in the machine", used by philosopher Gilbert Ryle to describe Descartes' theory of mind-body dualism. The pun refers to a shell called the Z shell, where the path to it can be shown as "/bin/zsh", as in the final panel. A shell is a program used to access the operating system.

The phrase "su to the user" can mean the act of switching to another user using the su command. The name stands for substitute user. If a superuser were to switch to another user, they can bypass the act of entering the user's password. The title text has further narratingon by the admin. They struggle to fight the urge to substitute as the user, as it could give the impression that Sam's ghost was using the account, which could shock the other server users if the action were to be logged or notified.

Transcript

[The text is over a white-on-black terminal showing a bit of output from ps -el | grep sam, with processes running from root and sam.]

When a user dies, their connections time out,

but their screen sessions linger.

[The end of the command line is a |grep sam.]

The server's uptime grows

because you can't bring yourself to reboot

and wipe out

their last earthly presence

[The processes listed are screen, zsh, irssi, and grep sam.]

the ghost in zshell.

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Discussion

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The explanation for comic 686: Admin Mourning was identified by Black Hat's Hat as being neglected and was nominated in August 2026 for This Week's Explanation for Improvement. It was considered as a candidate by the Explanation Improvement Project, but it was not successful. It remains open for any editor to expand, polish, and improve. (view the explanation at nomination time)

This reminds me of the philosophical thought that "...a person dies three times. The day he dies. The day the last person who knew him dies. The day his name is spoken for the last time." Makes you think, eh? 31.111.35.144 20:15, 15 May 2013 (UTC)

By "their screen sessions linger," does it mean litteral GNU Screen sessions? Ad1217 (talk) 04:00, 29 January 2014 (UTC)

Yes. SCREEN is in the greped output of ps in the comic 108.162.219.37 17:16, 31 January 2014 (UTC)

irssi (Internet Relay Chat client software) process running in SCREEN session possibly means that Sam is logged on to the IRC and appears as a live person on some talk channels. 141.101.97.202 (talk) (please sign your comments with ~~~~)

I'm not sure "old fashioned" is a correct description here. Modern Unix systems do this, too. 108.162.238.114 00:02, 8 August 2014 (UTC)

In my opinion this comic might contain a reference to the more or less popular movie "Ghost" (http://en.wikipedia.org/wiki/Ghost_(1990_film) ) as well, since the main character in this movie is called "Sam", too. --141.101.104.98 09:42, 21 October 2014 (UTC)
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