The history of Unix systems and their main components. Please DO NOT USE this tag for shell-related questions; use [tag:command-history] instead.

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21
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2answers
2k views

why is rm allowed to delete a file under ownership of a different user?

From the post Why can rm remove read-only files? I understand that rm just needs write permission on directory to remove the file. But I find it hard to digest the behaviour where we can easily delete ...
1
vote
2answers
741 views

Where does the word GNU come from?

GNU is a Unix-like operating system. That means it is a collection of many programs: applications, libraries, developer tools, even games. The development of GNU, started in January 1984, is known ...
1
vote
1answer
99 views

How can I find out the IP address from which a user logged in?

We have two RHEL 6.4 64-bit boxes in our environment. They are accessed remotely via putty. The password of user ABC on one RHEL box is shared by multiple users. User ABC logged into server from ...
2
votes
1answer
30 views

What is the meaning of the mode mask names from stat(2) and chmod(2)?

The stat calls have a series of symbolic names for the various bits in the mode field. From the stat(2) manual page: The following mask values are defined for the file mode component of the st_mode ...
2
votes
1answer
49 views

Why is the Intel HD Graphics driver called i915?

The only references to i915 I can find are indeed to the linux kernel driver for the intel chips. Intel just seems to call them HD graphics whatever. Intel 915 seems to refer to some Pentium 4 ...
2
votes
2answers
56 views

Why are certain naming conventions so inconsistent in Linux? [closed]

It seems like the general pool of logging, changelog, readme, and config files in Linux is very inconsistently named. It always makes me wonder, why didn't *nix devs decide on a common file name ...
6
votes
1answer
134 views

How were these Linux TCP default settings decided?

I spent quite some time tracking down a problem in production recently, where a database server disappearing would cause a hang of up to 2 hours (long wait for a poll() call in the libpq client ...
2
votes
1answer
49 views

Why is vdir still around?

After installing Debian 8, I started poking around /bin (as I'm always wont to do), and I noticed that ls and vdir share, not only the same manpage (except for the whatis line), but the exact same ...
24
votes
2answers
1k views

Patching a binary with dd

I have read this quote (below) several times, most recently here, and am continually puzzled at how dd can be used to patch anything let alone a compiler: The Unix system I used at school, 30 ...
33
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4answers
4k views

Why are UNIX/POSIX system call namings so illegible?

What is the reason to use such untelling system call names like time and creat instead of getCurrentTimeSecs and createFile or, maybe more suitable on Unix get_current_time_secs and create_file. Which ...
3
votes
1answer
48 views

Why should you avoid “stringently columnar” input formats?

Doug McIlroy, the inventor of Unix pipes and one of the founders of the Unix tradition, had this to say at the time [McIlroy78]: (ii) Expect the output of every program to become the input to ...
2
votes
1answer
226 views

sudo ls not showing hidden files on Linux

Today I discovered that sudo ls shows hidden files (that is, those that have names starting with .) on OS X. This surprised me so much that I asked a question about this behaviour, which I still find ...
6
votes
1answer
283 views

Why is the vi editor's copy command called Yank?

Why is the vi editor's copy command called “yank”? Is there any thing significant that can help me to remember the command name?
-1
votes
1answer
107 views

Who was the original author of logrotate and what year was it written?

The question started as an internal team debate. But we realized we couldn't find any information about when the original version of logrotate was authored and who wrote it.Do you have idea?
0
votes
1answer
64 views

deleting all occurences of a given command from history [closed]

I am trying to delete a specific entry in history. Clarification--by that I mean deleting all occurences containing a given command/or text. I used Aliteralmind's hxf script: :< Examples hxf ...
23
votes
2answers
515 views

Where is “export var=value” not available?

I have picked up -- probably on Usenet in the mid-1990s (!) -- that the construct export var=value is a Bashism, and that the portable expression is var=value export var I have been advocating ...
0
votes
0answers
29 views

What are the oldest irc clients I can still use on linux ?

I have a weakness for nostalgia and some interest in Unix history, therefore I would like to know which are the oldest still usable irc clients that can be run on Linux. In this context I value age ...
0
votes
1answer
51 views

important changes of linux 3.1 to 3.17 [closed]

I'm doing school research project for Linux operating system and I need help with summary of version 3.1 to 3.17. The problem is, I know very little about Linux and detailed technological terms used ...
8
votes
1answer
184 views

Why does brace expansion range use two dots instead of three (ellipsis)?

I finally understood/discovered why I never got to using bash's (and also zsh's) brace expansion range properly: the syntax is {1..10} instead of what I assumed to be an ellipsis, i.e. {1...10}. May ...
1
vote
0answers
61 views

how to copy files using TTY teminal from one pc to another connected through same home network

In my academic lab my friend copied files from one computer to another that were serially connected using the tty4. How could he have done this if there was no internet and he didn't install any new ...
2
votes
1answer
22 views

Why did “argument can be squisehd against option” prevail over “argument is always separate”?

Inspired by the recent question Why does the specific sequence of options matter for tar command?, in which the asker learned why tar -cfv test.tar *.jpg doesn't work, I'd like to ask a followup: ...
0
votes
1answer
92 views

Did Linux have a bug where reading /dev/null would crash the system?

About 10 years ago I've been told by someone that for years Linux used to crash whenever you tried to read /dev/null (ie. cat /dev/null). Is this actually true? Did such a bug exist? And if it did, ...
35
votes
1answer
4k views

Why is the UNIX system call kill named 'kill'?

I'm curious about the history of the name, it seems to me that the 'kill' system call could have been named 'signal', and the 'signal' system call could have been named 'handle'. I was wondering ...
1
vote
0answers
34 views

Is Cat-v.org an official subsidiary website of Plan 9 from Bell Labs?

I was wondering, since it seems to be one of the only websites where I can seemingly legally download historic Unix documents.
0
votes
2answers
84 views

what are considered old and powerfull commands? [closed]

I came across the terms awk and sed, awk goes once through all lines and performs a task whenever a line meets a certain condition, sed can manipulate a stream of input before it goes further to the ...
1
vote
1answer
276 views

Why has '-' been chosen as the backup file suffix for certain Unix system files?

Example: /etc/group-, /etc/passwd- Is there any motivation behind choice of the - sign (e.g. easier to recognize, process, etc.)?
5
votes
1answer
166 views

Why does 'find -exec cmd {} +' need to end in '{} +'?

Preface: I understand the difference between -exec {} \; & -exec {} +. I also don't have a problem as such, I am just curious about the semantics of find. When ending the -exec argument with + ...
6
votes
3answers
688 views

What's the rationale to have option to use power of 1000 instead of 1024 in df?

I'm curious about df -H and df -h, then man df tells me: -h, --human-readable print sizes in human readable format (e.g., 1K 234M 2G) -H, --si likewise, but use powers of ...
0
votes
1answer
67 views

Syntactic differences in cp -r and how to overcome them

Let's say we are in a blank directory. Then, the following commands: mkdir dir1 cp -r dir1 dir2 Yield two (blank) directories, dir1 and dir2, where dir2 has been created as a copy of dir1. ...
3
votes
1answer
75 views

Has Unix been used by accountants and other non-programmers at AT&T in the 70s and 80s?

In the short documentary, Ken Thompson and Dennis Ritchie Explain UNIX (Bell Labs) it is mentioned, that Unix is not only an OS, but also a system around which a community could form. I find ...
0
votes
1answer
172 views

What does “dd” stand for? [duplicate]

What does dd stand for? I've always referred to it colloquially as "Disk Destroyer", but what are the "official" words that make up the acronym/command? According to this link and this link it could ...
3
votes
1answer
107 views

The history of ../ [duplicate]

I was wondering if there's a known reason behind the use of .. to represent the parent of the current directory in most operating systems. The reason I ask this question is because I think that the ...
5
votes
1answer
165 views

What is ENOANO (No Anode) intended to be used for?

This question is merely for idle curiosity, but I suspect others will be curious as well. Searching through errno.h (of Linux 2.6) I found ENOANO "No Anode". There is no sign of a "No cathode" error. ...
3
votes
1answer
137 views

Can somebody list the earliest public source-code repositories and when they opened? [closed]

Nowadays people only know github, some people know gitlab, some people know bitbucket (mercurial) but other than that people seem to have forgotten there were others as well. I know about freshmeat ...
20
votes
3answers
449 views

How did the Linux Kernel project track bugs in the Early Days?

We all know that Linus Torvalds created Git because of issues with Bitkeeper. What is not known (at least to me) is, how were issues/tickets/bugs tracked up until then? I tried but didn't get anything ...
1
vote
0answers
24 views

history - bash, dash, zsh and .profile [duplicate]

For a long time I have been wondering about the existence of many shells in GNU/Linux. To make the question a bit focused I have used only three shells - bash, dash and zsh. From wikipedia articles ...
9
votes
1answer
203 views

Why didn't GNU Info succeed man?

As per my knowledge/understanding both help and man came at the same time or have very little time difference between them. Then GNU Info came in and from what I have seen is much more verbose, much ...
1
vote
1answer
119 views

Use case for /usr/bin/lessecho

I can not come up with an example of how I could/would use lessecho. The description in the man page is fairly straight forward but is not helping me come up with a use case: DESCRIPTION ...
3
votes
1answer
94 views

BSD Net/1 was a free fully operating system?

I think that the old BSD Net/1 was not a fully operating system, but an add-on to 4.3BSD for VAX, as I realize from http://gunkies.org/wiki/Net/1 and http://gunkies.org/wiki/Net/2 Is it right? In ...
-3
votes
3answers
503 views

Why is “shebang” called “shebang”?

Does "shebang" mean "bang she"? Why not "hebang" as "bang he"?
25
votes
1answer
1k views

When and how was the double-dash (--) introduced as an end of options delimiter in Unix/Linux?

I don't think the shell/utilities in historical Unix nor in something as "recent" as 4.4BSD supported using a double-dash(or two consecutive hyphens) as an end of options delimiter. With FreeBSD, you ...
2
votes
3answers
102 views

Why is NetworkManager package name upper case?

All other software packages are lower case, so why NetworkManager upper case?
32
votes
5answers
1k views

How to save a command you entered without executing it? [duplicate]

Every Linux user has experienced this annoying thing: you begin typing a long and boring command, then realise you should have executed another one before. How to save the first one to execute it ...
16
votes
2answers
2k views

Who is responsible for the Linux kernel?

As of today, there are many Linux distributions like Ubuntu, Fedora, Gentoo, Mint, Debian, etc. These distributions update at different cycles. Ubuntu seems to update its kernel weekly or monthly, ...
18
votes
1answer
1k views

If chown can change groups, why was chgrp created?

So there's chown which lets you change the owner and group of files and/or directories. But there's also chgrp which only changes the group. Why was chgrp created? Isn't it redundant?
7
votes
3answers
265 views

History of Bash globbing

Is there a historical reason why Bash "globbing" and regular expressions are not identical? For example, I believe that in Bash [1-2]* matches anything that starts with a 1 or a 2 followed by anything ...
3
votes
1answer
68 views

what is the original command to create a file? [closed]

we can create a file by a lot of commands: cat > foo.txt echo 'This is a test' > foo.txt touch foo.txt vi foo.txt (or any text-editor) my questions are: What is the original command to ...
5
votes
2answers
451 views

Why wasn't `creat` called `create`? [duplicate]

Was it just to save typing one letter? I don't think C function names were limited to five characters at the time, as strcmp and unlink are probably just as old. I'm hoping someone who was involved ...
3
votes
2answers
2k views

What does chmod stand for?

In order to memorize a command, it is usually a good idea to learn where it's name comes from. For example, cp comes from copy. usermod means "User Modifiy" (at least I guess so). Where does chmod ...
10
votes
2answers
203 views

Possible to see dead proccesses?

In man ps, it clearly states the different states a process can have on Linux. D Uninterruptible sleep (usually IO) R Running or runnable (on run queue) S Interruptible sleep (waiting for an ...