Unix and Linux Stack Exchange
Unix and Linux Stack Exchange

Questions tagged [reference]

Resources, online or offline, that contain information relevant to specific subjects or would provide context for understanding Unix and GNU/Linux.

28 questions
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Resources for portable shell programming

What resources exist for portable shell programming? The ultimate answer is to test on all targeted platforms, but that's rarely practical. The POSIX / Single UNIX specification is a start, but it tells neither you what the level of support of each…
Gilles 'SO- stop being evil'
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Is there a tool/website to compare package status in different Linux distributions?

I am currently looking for a website or a tool that would allow me to compare the package state of a particular software in different Linux distributions. For instance, which version of gimp is provided by Mint, Ubuntu, Debian Sid and Fedora 18? An…
Thomas Moulard
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/etc/hosts file refer to another configuration file

How can I get the /etc/hosts file to refer to another configuration file for it's list of hosts? Example /etc/hosts: ## My Hosts 127.0.0.1 localhost 255.255.255.255 broadcasthost #Other Configurations
DogEatDog
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Best resources to learn bash scripting?

I've programmed in a number of languages for two years now, I mean that I know how to design and implement a decent solution for a given problem. However, bash is being a major headache to me, just nothing does work as expected—or even without…
deprecated
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Is there any documentation for udev builtins?

The man page for udev mentions in several places that certain rules options can be used to invoke 'builtin' commands, which are apparently built in to the udev program itself. However, I haven't been able to find any reference documentation that…
Time4Tea
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Who decided the bc math library will define sine cosine and arctangent?

If you load the bc math library you get the trig functions s() and c() and a() which are sine, cosine, and arctangent respectively. Why these three functions? I know why it's those three from the mathematical perspective: it's because those are the…
Mike Pierce
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How do I find a command if I don't know its name?

As a Unix beginner, I often find myself wanting to know the name of the command that achieves a particular function I'm after. How can I go about finding out the name of the command, given a description of what it does?
Zaid
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EXT3 file system pre digest material

I am looking for understanding EXT3 filesystem source code. I think I need a little pre-digestion to fully understand the code. Can anyone please suggest some material(blog etc.) where I can get some basic understanding of the source code.
Manish
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retrieve bash array by referencing its name as a variable

I need help with bash expansion. I want to retrieve array values, GNU bash 5.1.0. The array name shall be a variable. "Just" referencing a variable in bash. I have an array named "armin" and its name is in variable $gral (works…
opinion_no9
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What has happened w.r.t books about linux device driver programming in the last eight years?

This is probably a silly-sounding question, but one that I think there exists an objectively right answer to which makes me compelled to ask it. I am trying to understand the fundamentals of linux systems and especially how device drivers work so I…
embedded_crysis
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Unix dictionary add-on for Mac OS "Dictionary" app?

I've seen there's other dictionaries you can add to OS X's Dictionary app, but all I can find is spoken languages. It'd be nice to, while reading a software book, be able to right click a unix function/keyword/etc and have it come up in Dictionary.…
Marty
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Is a NEWLINE character at line end required by LSB (Linux Standard Base)?

Both POSIX and SUS (Single UNIX Specification) define a line as A sequence of zero or more non- characters plus a terminating character. Many distributions are more oriented towards LSB than POSIX. LSB includes a lot of…
Mario Nette
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Argon2 Commands in the Terminal

I have been using Argon2 in my terminal (Debian), but I keep messing up, and I have been unable to find the manual or any other documentation that lists examples of commands that work. Could someone give me a basic rundown of what the most important…
Patriot
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I am having difficulties with back-reference in awk

Recently, I am into security logs and want to make it better way on bash-shell. I found out in awk back-references are only stored by 9. But I need to use 10 back-references. Tried awk '{print…
KeiTheNoop
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how to get the size of an indirect array in bash?

Without using eval. this wont work: astr=(a b c) str="#astr[@]" echo "${!str}"
Aquarius Power
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