The Dash shell, a POSIX-compliant derivative of the Almquist shell used as /bin/sh in Debian, Ubuntu and other Linux distributions

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Will I be able to build LFS using dash and mawk?

I decided that I want to learn more about Linux and try building LFS. I'm using Ubuntu 11.04 as host system and Ubuntu uses dash and mawk by default. I've changed mawk to gawk, but considering that ...
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Get line number in a Bourne shell script

I'd like to be able to print the current line number in a shell script. I know about the $LINENO variable in Bash shells, but it doesn't seem to exist in Bourne shells. Is there any other variable ...
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When sh is a symlink to bash or dash, bash limits itself to POSIX-compliance, so it should be 100% compatible with sh?

From Difference between bash and sh: ABck to the question: If you have /bin/sh as a link to bash, then bash will not behave the same when called as /bin/sh as it does when called as /bin/bash. ...
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A couple arithmetic related commands, Dash, POSIX shell, sh, Increment

When pre/post incrementing a variable, in POSIX Shell, what is the difference between these two examples. They seem like they would have the same consequences, but would they be used differently? ...
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971 views

In a script, check if standard input comes from a file or pipe

I know this has been poorly covered previously, but those answers either lack explanation or don't apply. Basically at some point my scripts needs check if a file is specified, if it was it will be ...
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Why does this incrementing for loop return a bad variable?

I'm trying to call this shell script from within the CLI of GRASS GIS: for (( day=5; day<367; day+5 )); do # commands that I've tested without a loop. done exit 0 returns Syntax error: Bad ...
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How to pkill from a script?

How can I write a script that basically just runs pkill -HUP inetd? I want to restart inetd via a script so I can schedule it to run at a particular time. I tried to write it myself, but I'm getting a ...
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Shell script error message

I am trying to learn shell scripting by reading linuxcommand.org. For some reason I keep getting the error "Not Found", even though it runs all the commands. The error codes I get are: ...
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Getopts option processing, Is it possible to add a non hyphenated [FILE]?

I'm using getopts for all of my scripts that require advanced option parsing, and It's worked great with dash. I'm familiar with the standard basic getopts usage, consisting of [-x] and [-x OPTION]. ...
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Can I trace a dash script without modifying its source code?

I would like to trace a shell script for debugging purposes without having to modify its source code (e.g. change the shebang or insert a set -x at the beginning). It is a dpkg postinst script, so not ...
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How does this bash function work?

I'm looking at this short example, and I don't see how this function works: function EXT_COLOR () { echo -ne "\[\033[38;5;$1m\]"; } AFAIK -ne stands for not equal. What are we comparing here? I ...
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dash compatibility to bash

Wikipedia says that dash executes faster than bash. My question is, if I set /bin/sh to dash, will all scripts that use /bin/sh in their shebang line that was intended for bash work under dash?