The history of Unix systems and their main components.
301
votes
2answers
72k views
Design question: Why was '~' chosen to represent the home directory?
I have often wondered why the ~ represents the home directory of a user. Is there a reason behind this? Or is it just some infrequently used character?
54
votes
2answers
3k views
49
votes
6answers
5k views
Is Linux a Unix?
So, there are lots of different versions of Unix out there: HP-UX, AIX, BSD, etc. Linux is considered a Unix clone rather than an implementation of Unix. Are all the "real" Unices actual descendants ...
47
votes
5answers
9k views
Where did the “wheel” group get its name?
The wheel group on *nix computers typically refers to the group with some sort of root-like access. I've heard that on some *nixes it's the group of users with the right to run su, but on Linux that ...
27
votes
5answers
1k views
Why is there a * When There is Mention of Unix Throughout the Internet?
I've noticed that throughout the Internet, within forums and blog posts, Unix always has a * in the word, whether it is *nix or Un*x, as I noticed at the welcoming banner at the Unix StackExchange ...
26
votes
2answers
1k views
Why is 'umount' not spelled 'unmount'?
I am wondering if there is any historical or practical reason why the umount command is not unmount.
22
votes
5answers
2k views
Why do /usr and /tmp directories for Linux miss vowels in their spellings?
I have often started to think about this but never found a good answer. Why are these two Unix directories not /user and /temp instead?
All the other directories under root seem to be exactly what ...
22
votes
3answers
2k views
What did Ken Thompson mean when he said, “I'd spell create with an 'e'.”
Ken Thompson, the creator of Unix, was once asked what he'd do if he had
it to do over again. He said, "I'd spell create with an 'e'."
What is Ken referring to? Is there a "creat" command?
20
votes
1answer
628 views
Why was '.' chosen to represent the current directory and '..' for parent directory?
After reading this question Design question: Why was '~' chosen to represent the home directory?, next obvious question on my mind was why '.' and '..' was used to represent current directory ...
17
votes
4answers
640 views
What aspects of Plan 9 have made their way into Unix?
Plan 9 was developed by Bell Labs as a successor to Unix. Although for various reasons it never quite materialized as such, a fair amount of development still went into Plan 9.
My question is, what ...
16
votes
1answer
492 views
What shells were used on early unix systems?
According to wikipedia, the Bourne shell was introduced in 1977 and C shell in 1978, but unix itself dates back to 1969.
If you were using a unix system before 1977, what shell would you have been ...
16
votes
0answers
473 views
How did the system settings directory on UNIX come to be named /etc? [duplicate]
Possible Duplicate:
What does etc stand for?
And why isn't it named /cnf or /syscf or /cfg? No one I have ever asked has been able to tell me, not that I have access to any of the minds ...
15
votes
2answers
1k views
Origin of 'root' account
What's the origin of root account? Where did it come from and why is it called root anyway?
(Originally asked by @lizztheblizz on Twitter.)
15
votes
1answer
625 views
Weird file in the /usr/games folder of Ritchie's 1979 unix disk
I recently tried the simh emulator pdp11.
The disk image I used can be found on the internet, and instructions for booting it are here.
Presumably it belonged to Dennis Ritchie, as the username is ...
14
votes
2answers
2k views
Why does Unix time start at 1970-01-01
Why does Unix time start at 1970-01-01? Why not 1971-01-01 or any other date?
12
votes
2answers
507 views
What is a socket?
Could someone explain to me what a socket is? I see it in many acronyms in context of SSL, etc.
Also, why is it called a socket? Is it purely because it was what a name they invented? Or was it the ...
11
votes
2answers
374 views
Why is JFS so obscure?
When I first got into using Slackware years ago I quickly learned to love JFS over ext3 or reiserfs given that it was reliable and if there was an unclean shutdown, its disk checking was very very ...
11
votes
1answer
253 views
What is the difference between shared memory in early unix systems vs modern unix systems?
How could processes share memory in early versions of UNIX version modern implementations of shared memory?
11
votes
2answers
542 views
Origin of the word cron?
Trying to settle a friendly argument. Is "cron" an acronym for something?
Additionally, did it's current canonical name "cron" originate from something shortened for something like chronos or ...
10
votes
4answers
760 views
How did they manage to drive a Unix computer before mice and copy & paste?
Since Unix is 40 years old, Unix is older than the invention of the computer mouse. (actually only 3 years if Unix is from 1969 and the mouse from 1972) How in the world did a new user do anything ...
10
votes
4answers
549 views
Single dashes `-` for single-character options, but double dashes `--` for words?
Where did the convention of using single dashes for letters and doubles dashes for words come from and why is continued to be used?
For example if I type in ls --help, you see:
-a, --all ...
10
votes
3answers
437 views
How was the shift to 64 bits handled on Linux
How was the transition to 64 bits handled on Linux/Unix? The Windows world still seems to have issues with it and I'm curious how it was handled in the *nix world.
10
votes
2answers
192 views
Why do Unix man pages use double backticks in place of double quotes?
I've noticed that man pages and other documents formatted by Unix utilities often use double backticks `` followed by double single quotes '' to wrap quoted phrases instead of the double quote ...
10
votes
1answer
329 views
What do all the pictures on the front of the “Unix and Linux System Administration Handbook” represent?
I'm a newcomer to Unix and Linux, and I've been trying to get up to speed on everything. One of the guides I've used is the "Unix and Linux System Administration Handbook"
It's a pretty great book, ...
8
votes
3answers
320 views
Why do we need the reboot function in different binaries?
Why do we need the reboot function in different binaries?
shutdown -r
and
reboot
Or do they differ in something?
7
votes
2answers
737 views
What is Unix now?
As I read in Wikipedia, Unix started as a revolutionary operating system written mostly in C allowing it to be ported and used on different hardware. Descendants of Unix is mentioned next, mostly BSD. ...
7
votes
2answers
981 views
What are the main differences between BSD- and linux-based operating systems?
I am a long time linux user and have recently become interested in playing about with BSD-based operating systems. What are the differences between linux and BSD-based systems. I am interested in ...
7
votes
2answers
251 views
Unix History: return code octal?
// EDIT: Request to move this question to unix.stackexchange.com
I was thrown off guard today by gdb:
Program exited with code 0146.
gdb prints the return code in octal; looking into why I found:
...
6
votes
3answers
1k views
What is the point of the 'operator' user?
Many un*x systems ship with a user account named 'operator'. What is the purpose of this account?
Do some systems actually make use of this account, or is this more of a historical legacy? Have you ...
6
votes
2answers
2k views
Is `cal` broken? What happened in September 1752?
If you look at the output of cal 9 1752 you will see this strange output:
September 1752
S M Tu W Th F S
1 2 14 15 16
17 18 19 20 21 22 23
24 25 26 27 28 29 30
The following story ...
6
votes
2answers
453 views
Is it true that the first version of Linux was based on parts of Unix?
Me and a friend had a discussion about Linux and Unix today and my friend kept saying that the first version of the Linux kernel was based on [parts] of the Unix kernel.
This really surprised me ...
6
votes
3answers
130 views
Did all of the Requests for Comments directly affect the design of Unix networks?
I want to know more about Linux must be one of my most enduring sentiments.
But I often find that I learn the most, or perhaps just feel the most satisfied with what I have learned, when I simply ...
6
votes
2answers
237 views
Why are UNIX logins often formed with the first letter of the first name followed by the first seven letters of the name?
I have seen in many places (especially universities) logins formed in the following way:
First letter of the first name: John Smithsonian → j
First seven letters of the name: John Smithsonian → ...
6
votes
2answers
92 views
Expand subshell before executing it?
I often run commands using subshells, and sometimes would like to have the subshells expanded before I run something.. This way I could verify what I'm doing, and possibly edit what's about to happen ...
6
votes
2answers
118 views
When was the concept of remote repositories invented?
When were remote repositories, for any package manager, invented and implemented?
6
votes
1answer
303 views
Who are these BSD Unix contributors?
I'm trying to piece together the names of the people who contributed to BSD Unix, according to the contents of the SCCS logs. (This is the version control system used at the time.) A number of names ...
5
votes
5answers
601 views
If Mac OS X is UNIX, why is it that it is not open sourced and the license is proprietary?
If Mac OS X is a Unix, as answered in this question, why is it that it is not open sourced and the license is proprietary, as stated in this Wikipedia article?
According the the genealogy from this ...
5
votes
3answers
151 views
When was process substitution first introduced?
I'm curios to know how long process substitution has been around. What shell first had it? When did it get added to other shells?
5
votes
1answer
422 views
Anyone know the meaning of yy?
Since history questions are considered on topic, I figured I'd ask one that's been bugging me for quite some time and no one I know seems to know the answer. Does anyone know what the historical ...
5
votes
3answers
122 views
When were the first graphical app installers created for Linux distributions
Having a discussion at work with a colleague, and he is claiming graphical installers for *nix environments have only been available for the last few years, but I can't find any solid information on ...
5
votes
3answers
401 views
zsync vs. jigdo
What's the difference between zsync and jigdo? Their core functionality seems the same, so I'm curious on things like performance, file size, and ease-of-use. Would also be interesting to know why one ...
5
votes
1answer
165 views
What are the origins of rgb.txt?
Where did the list of X11 color names come from? Every resource I've found online claims the origin is unknown, but it must be recorded somewhere. The best information I've found was in an archived ...
4
votes
4answers
2k views
Evolution of Operating systems from Unix
Can you explain the evolution hierarchy of operating systems (Linux and Windows) from Unix?
4
votes
2answers
1k views
4
votes
3answers
226 views
Is `Tru64 UNIX` open source?
Is Tru64 UNIX an open source/free or commercial system? Does it work on 32-bit platform? and what are its features in compare with *BSD & Linux system?
4
votes
2answers
417 views
Why does the “she-bang” begin with a “#!”?
Why does the "she-bang" begin with a #!, like #!/bin/bash? I have always accepted that this how it is done, but is there a reason behind it?
Why start with #; isn't that usually a comment? Or is it ...
4
votes
3answers
70 views
CD into directory from HISTORY in a bash script or alias e.g. $(!!)
I often want to change into the directory of a file on my file system, but I'm not sure where the file is.
I search for it like so:
find -type f -name "myfile.txt"
Lets say for the sake of ...
4
votes
2answers
683 views
4
votes
2answers
161 views
What are all the items on the cover of the “Linux Administration Handbook”?
As I mentioned in What do all the pictures on the front of the "Unix and Linux System Administration Handbook" represent? I'm fairly new to Linux and Unix.
@jasonwryan provided an excellent ...
4
votes
1answer
133 views
History of apropos command
I am writing a paper on my project, the goal of which is to write a new implementation of the apropos(1) command. While I realize that apropos was written in the early days of Unix when computing ...
