Questions tagged [conventions]

Naming conventions and best practice

66 questions
212
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4 answers

Why do we use su - and not just su?

I don't understand why su - is preferred over su to login as root.
Dharmit
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66
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8 answers

Why does Bash's source not need the execution bit?

With Bash's source it is possible to execute a script without an execution bit set. This is documented and expected behaviour, but isn't this against the use of an execution bit? I know, that source doesn't create a subshell.
Motte001
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65
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2 answers

Why are shared libraries executable?

Why have almost all the shared libraries in /usr/lib/ have the executable permission bit set? I don't see any use case for executing them. Some do manage to hook-up some form of main function to print a short copyright and version note, but many…
61
votes
17 answers

Why do Unix-heads say "minus"?

A couple of weeks ago I attended a talk on Git by someone who seemed to be from a Windows background. I say "seemed to be" because he kept saying "dash" when referring to command-line options. I then recalled something that I found curious in my…
Eric Smith
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57
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7 answers

File extensions for unix shell scripts

On wikipedia, the article for .sh says: For the .sh file extension type, see Bourne shell. How about other unix shells? I know that the shebang is used inside the file to indicate an interpreter for execution, but I wonder: What are the pros…
Amelio Vazquez-Reina
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30
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10 answers

one-liner vs script

I've noticed a lot of questions and answers and comments expressing disdain for (and sometimes even fear of) writing scripts instead of one-liners. So, I'd like to know: When and why should I write a stand-alone script rather than a "one-liner"? …
cas
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28
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3 answers

File and directory naming conventions

I want to refactor the files and directories on my system. However I am not sure what is best practice. After reading this question and its answers I assume the most important part is to be consistent. However, this is where I'm stuck. E.g. in root,…
whirlwin
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26
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3 answers

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 chronological? A quick google search didn't find what i…
chrisjlee
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26
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1 answer

What is the number prefix in config files from .d directory

A lot of unix config files in xx.d folders are prefixed by a number, like : $ ls /etc/grub.d/ 00_header 10_linux 30_os-prober 40_custom 05_debian_theme 20_linux_xen 30_uefi-firmware 41_custom Is there any convention on this…
Rémi Benoit
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21
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2 answers

An official standard / convention for a file extension for shell scripts to source

I was wondering if there is a convention for file type extensions for shell scripts you want to source instead of run. For example: If I want to run this script in a subshell. ./script.sh If I want to remember to run this script from the…
Mateusz Piotrowski
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13
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2 answers

When to use standard error stream in command-line application?

Is there a guideline when to use the error when writing a command-line application? To my surprise, I didn't find anything when googling it. In particular, the question I'm concerned with right now is whether to use stdout or stderr when the user…
UTF-8
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12
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2 answers

Convention/standard on using curly braces around options

The man page for tar in Arch Linux SYNOPSIS section starts with: tar {A|c|d|r|t|u|x}[GnSkUWOmpsMBiajJzZhPlRvwo] [ARG...] I perfectly understand that in this situation it means that exactly one of the options in the curly braces must be given…
umbasa
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10
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2 answers

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 significance is of the prefix yy? Most of the…
Timothy
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10
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1 answer

When should you use subshells vs `xargs`?

Many simple commands using xargs could be rewritten as commands using subshells. For instance, here is something I was using earlier today, to concatenate the ten largest binaries in /usr/bin, written using a subshell vs xargs: subshell: $ cat $(du…
haneefmubarak
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9
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2 answers

Where should I mount my external harddrive?

I've got an external harddrive that I'd like to auto-mount. It will be present most times when my laptop boots. Where is the "correct" place to mount it? /media/my-hd: Will litter /media with an empty folder when the hard-drive was not…
Anna
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