POSIX is an acronym for "Portable Operating System Interface", a family of standards specified by the IEEE for maintaining compatibility between operating systems.

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POSIX and Bash, sh shorthand, for compound if statement

I prefer to do my sh commands in shorthand, And I prefer to be in POSIX. Truthfully, if the script can run on Dash, that is good enough. Which means using the test command [, not the extended [[. I ...
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Why not just use standard streams instead of using filenames?

While I understand that programs like mv need an actual filename as a parameter, programs like sort could just read from standard input and write to standard output like names | sort > names ...
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Why do some applications use ~/.config/appname for their config data while others use ~/.appname?

I've noticed that some applications put their configuration files to ~/.config/appname while others use ~/.appname (the classic way, AFAIK) for this. What's the sense in this distinction and what ...
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Should I end my text/script files with a newline? [duplicate]

Possible Duplicate: What's the point in adding a new line to the end of a file? What is considered better behaviour: to leave the last letter of the last line to be the last byte of a ...
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Newlines in filenames

I understand and accept the premise that defensive1 shell scripting is both prudent and, in the longer term, more sustainable. Many of the answers to text processing questions here follow this ...
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Where can I find official POSIX and UNIX documentation?

I am looking for official documents on all POSIX standards and specifications. I would like to be able t read the docs to get a better understanding of UNIX systems and how they work at a low level. ...
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Open Group Base Specifications, Single UNIX Specification and POSIX [duplicate]

Possible Duplicate: What differences are between POSIX and Single UNIX Specification? Having asked about the relation between POSIX and Single UNIX Specification, I was now wondering what ...
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Difference between POSIX, Single UNIX Specification, and Open Group Base Specifications?

What are the differences between POSIX, the Single UNIX Specification, and the Open Group Base Specifications? I think their purpose is for determining if an OS is Unix?
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What exactly is POSIX?

I see POSIX mentioned often and everywhere, and I had assumed it to be the baseline UNIX standard.. until I noticed the following excerpt on a Wikipedia page: The Open Group The Open Group is ...
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What does 'uni' mean in unistd.h

What does uni mean in unistd.h Does it mean unix? or universal? What is it?
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How do I test to see if an application exists in $PATH?

I'm trying to write all of my sh startup/env scripts to work with as much DRY and as much: "works on every *nix I clone it to", as possible. This means making sure that if I try to run code that's not ...
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Why does the local::lib shell code use eval and $()

using local::lib requires you to add a line to your ~/.shellrc eval $(perl -I$HOME/perl5/lib/perl5 -Mlocal::lib) I don't understand what the point of using eval, and encasing the statement in $() ...
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keep duplicates out of $PATH on source

I have the following code that's source-d by my .shellrc PATH="${PATH}:${HOME}/perl5/bin" PATH="${PATH}:${HOME}/.bin" export PATH but if I make changes to other code and then source this file, my ...
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$VAR vs ${VAR} and to quote or not to quote

I can write VAR=$VAR1 VAR=${VAR1} VAR="$VAR1" VAR="${VAR1}" the end result to me all seems about the same. Why should I write one or the other? are any of these not portable/POSIX?