Questions about bash only, as opposed to other Bourne/POSIX shells. For all Bourne/POSIX-style shells, use the /shell tag instead.

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3
votes
5answers
5k views

How to find out what version of RHEL I'm using?

I work in an environment where we are slowly transitioning machines from Red Hat Enterprise Linux 5 to RHEL 6. I need some of my scripts to do something subtly different on RHEL6 machines to what is ...
7
votes
2answers
206 views

Different colour for the KiB range in `ls -l`

Is there any sane way to highlight the 4th, 5th, and 6th columns from the right of the file size in ls -l? My intention is to make it easy to read a file size be it in bytes, KiBs, or MiBs. I do know ...
1
vote
3answers
509 views

VIM only files, cd only directories

When using Tab for completion on the Bash shell prompt, is there any way to configure it to complete only files for the command vim and only directories for the command cd? In large directories with ...
3
votes
2answers
518 views

Bash: passing braces as arguments to bash function

I love using the following pattern for searching in files: grep --color=auto -iRnHr --include={*.js,*.html,} --exclude-dir={release,dev,} "span" . I'd like, however, to have this one wrapped into a ...
2
votes
1answer
323 views

Add echo command to /etc/profile to disable screen blanking

I am considering adding the following echo command to /etc/profile echo -e ‘\033[9;0]\033[14;0]’ The system in question does not have setterm command available and is just running text console. ...
0
votes
1answer
759 views

Login script for bash not loading

I am very confused about the login script for bash. I have always used ~/.bash_profile to configure my bash shell. Now I am on a new system just as a user: I am not root. This system was originally ...
4
votes
1answer
539 views

Coloring shell command and output differrently [duplicate]

Possible Duplicate: Customizing bash shell: Bold/color the command bash $ cat what-i-want "I want the output be in a different color." I'd like my commands stand out among the output, ...
1
vote
2answers
875 views

bash scripting - Any function to escape character?

I am trying to automate some of my stuff and facing a issue, the problem boils down to escaping the value that is being passed as a argument to the script. myScript.sh #!/bin/bash loadPatch -name ...
4
votes
1answer
4k views

What's the command to “prepend” a line to a file? [duplicate]

Possible Duplicate: How can I prepend a tag to the beginning of several files? Other than create a temporarily file with a line at the heading, and move it back when finished, is there a ...
2
votes
1answer
430 views

Is there a way of color-highlighting paired brackets in shell (bash)?

Does anyone know if there is a way reproducing the same behaviour many text editors provide for colour-highlighting the syntax operators such as brackets or curly brackets. It would be very useful for ...
1
vote
2answers
551 views

How can I find matches with sed (or similar) for configuration parameters?

I'm pretty good at using php's preg_match (and similar) commands, and I'm also pretty good with regular expressions, but I don't do very well with sed. I have two shell scripts I'm working on and I'd ...
4
votes
0answers
23 views

Forward Autocorrect to a script [duplicate]

Possible Duplicate: How do I get bash completion for command aliases? I wrote a series of scripts to make package management a little more intuitive for me. However, I can no longer tab ...
2
votes
1answer
388 views

Display 'PRI' and 'NI' via 'top -stats'

I'm trying to create a script that prints top stat for some specific fields (e.g. pid, command, priority, nice value). I can print most of them by using -stats option, but there is no arg for ni and ...
3
votes
1answer
314 views

Why is not every variable initialized to its data type specific default value upon declaration in Bash?

When I execute the following code in Bash version "GNU bash, version 4.1.10(4)-release (i686-pc-cygwin)", I get: declare a declare -p a # Output: -bash: declare: a: not found declare -i b declare -p ...
7
votes
3answers
13k views

How to test if a variable is defined at all in Bash prior to version 4.2 with the nounset shell option?

For Bash versions prior to "GNU bash, Version 4.2" are there any equivalent alternatives for the -v option of the test command? For example: shopt -os nounset test -v foobar && echo foo || ...
3
votes
2answers
3k views

How do I parse namespaces from an XML file using XMLLINT and BASH

Below I have an example of an Adobe XML swidtag used to track inventory. I need to parse out relevant information using xmllint in bash and output that to a new text file. For example I would like ...
0
votes
1answer
763 views

Unable to loop through cURL command

I am able to execute individual cURL commands using, curl -u user:password -v -XPOST -H 'Content-type: text/xml' -d '<featureType><name>quadrella_indica</name></featureType>' ...
1
vote
1answer
496 views

How to initialize a read-only, global, associative array in Bash?

I execute the following code in Bash version "GNU bash, Version 4.2.39(1)-release (x86_64-redhat-linux-gnu)": function foobar { declare -rgA FOOBAR=([foo]=bar) } foobar declare -p FOOBAR # Output: ...
8
votes
3answers
6k views

adding text to filename before extension

I would like to add text to the end of filename but before the extension. Right now I am trying, for f in *.shp; do echo $f_poly; done the output is, Quercus_acutifolia.shp_poly ...
0
votes
4answers
710 views

Bash Globbing Variable Substitution? [duplicate]

Possible Duplicate: Batch renaming files I want to rename files using their existing name as a base for the new one. So if I can ls these files with ls blue*+(.png) I'd want to rename ...
2
votes
1answer
721 views

What happened to ~ when updating oh-my-zsh?

Not sure what changed the meaning of the home path ~ in my zsh. So when I do cd ~ , I dont cd into my home but it gives me an error that /Users/carlos does not exist. How can I reset ~ to refer to ...
1
vote
2answers
6k views

Get PID of a function executed in the background

#!/bin/bash function abc() # wait for some event to happen, can be terminated by other process { sleep 3333 } echo "PID: $$" abc & echo "PID: $$" I need to retrieve the pid of this function, ...
2
votes
2answers
374 views

How can I create an alias synonym?

I have an alias pwd How can I create another alias that is a synonym for it? For example I have alias cd1='cd ~/dir1' I want a second alias cd01 that points to the same place but I don't want to ...
0
votes
2answers
252 views

Why doesn't Bash accept `&>&3`, i.e. redirecting stdout and stderr to file descriptor 3?

Given the preamble, foobar function and invocations of it: exec 3>/dev/null function foobar { echo foo; echo bar >&2; } foobar >/dev/null foobar 2>/dev/null foobar ...
3
votes
3answers
223 views

Bash port auto upgrading script in cron doesn't work properly?

I've been recently try to write a script to automate checks for new version of ports and software installed on my FreeBSD server. This script is added to root's crontab and fires daily. If I run it ...
2
votes
2answers
121 views

Bash Vi-mode: Move back to last slash

I'm using Bash in vi mode with set -o vi. Often I re-run a command but need to change the name of a file in the same directory. Example: mv /tmp/myfileA.txt /home/daniel/myfileA.txt Then, I ...
18
votes
3answers
902 views

What is the difference between [[ $a == z* ]] and [ $a == z* ]?

Is there is any difference between these two. [[ $a == z* ]] and [ $a == z* ] Can I have an example where they would have different outputs? Furthermore, how does the working of [[ ]] differs ...
2
votes
2answers
1k views

Sort the output of find before piping to openssh

I'm using this command to recursively generate a SHA-512 hash for each file in a directory hierarchy: find . -type f -exec openssl sha512 {} \; I'd like to sort the files in lexicographical order ...
2
votes
1answer
520 views

Redirect all standard out for rest of script

I have a bash script that I want to redirect all the rest of the output into a file. #!/bin/bash # the part i dont know ${file} echo spo echo car cat ${file} output should be spo\ncar\n
1
vote
3answers
2k views

How can I use grep to search for lines that start with a certain character in bash

I want an alias ('ggg') that will look through my existing set of aliases and tell me all the ones that begin with g. I have a lot of g* aliases :) I tried this: alias ggg='alias | grep ^g' but ...
1
vote
3answers
4k views

Print lines where first field has only four characters using regex in awk?

John Goldenrod:(916) 348-4278:250:100:175 Chet Main:(510) 548-5258:50:95:135 Tom Savage:(408) 926-3456:250:168:200 Elizabeth Stachelin:(916) 440-1763:175:75:300 output should contain the lines ...
1
vote
2answers
4k views

how do I run a cron job with a specific user?

My cron and scripting skills are very poor, but I need to run a job every 5 minutes by user 'cpc'. So I created a script and left it at /root. My crontab -e entry about it is: 0-59/5 * * * * ...
1
vote
1answer
479 views

How to delete a file to the trash in BASH (Linux) [duplicate]

Possible Duplicate: Make `rm` move to trash I've looked everywhere for the answer, but I can't find it. Is it possible to move/delete a file to the trash folder on linux. But also having ...
2
votes
2answers
2k views

Shell - Deal with multiple command history files

Where I work, for security and auditing purpose, we have to keep one history file for each session (user, date, terminal, etc in the file name). Obviously, the HISTFILE variable, is set to read only ...
3
votes
1answer
1k views

Modify /etc/xdg/lxsession/LXDE/autostart before boot

I have some parameters that I would like to change in /etc/xdg/lxsession/LXDE/autostart, before it is run. I get the parameters from a grep command. I would like to feed them to the autostart file but ...
1
vote
2answers
2k views

appending a variable to a file in Bash not working

I have a code like this #! /bin/bash $version = "1.0"; $preffix = "ApplicationName."; for f in pack*; do echo "bla bla bla" > myFile.txt echo $preffix >> myFile.txt echo "more ...
4
votes
2answers
179 views

Highlight path separators in PS1

I want to do something like this in Bash: how to format the path in a zsh prompt? But everything I try results in the PWD being fixed to the first directory I start my terminal in. Strangely I've ...
1
vote
1answer
155 views

What's the essential difference between grep foo $(CMD) and CMD | grep foo

It's really important because intuitively they are all similar for me. Could one realise that those two are really like one another for me, i.e. absolutely equal?
6
votes
4answers
751 views

Bash prompt that won't clobber long commands

I'm trying to set up a bash prompt for - hostname(screen#):directory$ which is coloured green if the last command completed successfully, red if not. This is what I have so far, which actually does ...
4
votes
2answers
934 views

Log number of keyboard hits

How can I log a keyboard hit via shell script? My aim is to log the number of keyboard hits of a login session on my Ubuntu system. Note: I do not want to log the keystrokes itself, only the number ...
2
votes
2answers
145 views

Zipping files two by two

I have a directory that has 800 files like this: file1.png file1@2x.png file2.png file2@2x.png file3.png file3@2x.png ... etc I need to create zip files like this file1.zip (containing ...
1
vote
1answer
129 views

renaming diverse files

I store files named like this: word-word2-word3-word4.txt . The number of "words" varies from file to file. I want to replace certain of the dashes with pluses e.g word+word2-word3+word4.txt I want ...
1
vote
2answers
2k views

How to avoid cp -r ~/some/folder/ . copying all files to the current folder's top level?

(Update: this happens on Mac OS X -- I am using Mountain Lion.) It sometimes happen that I use the tab key to complete the path, so my command may be: cp -r ~/some/folder/ . but it turns out that ...
8
votes
1answer
545 views

Why does this PS1 value cause unexpected behaviour? [duplicate]

Possible Duplicate: Why is my bash prompt getting bugged when I browse the history? I have set my PS1 variable in .bashrc to be the following: PS1='\e[35m[\W]:\e[0m ' It achieved what it ...
2
votes
2answers
181 views

Where to place a Bash shell redirection for a command? [duplicate]

Possible Duplicate: Order of redirections Apart from the standalone exec >&2 to redirect the current shell's input and output are there any behavioral differences in the following ...
1
vote
4answers
1k views

Check if the residence's connection has internet access

I'd like to be able to test if I have access to the internet. My computer is connected to the residence internet connection. I thought of using ping like this: ping -q -w 1 -c 1 `ip r | grep default ...
9
votes
4answers
1k views

Avoiding errors due to unexpanded asterisk

In bash I often use for-loops such as the following for file in *.type; do sommecommand "$file"; done; to perform an operation for all files matching *.type. If no file with this ending is ...
2
votes
3answers
370 views

How to read '\n' into variable with Bash's built-in command?

Somehow I'm not able to read the trailing \n sign into the REPLY variable. Under any circumstances I want to avoid a blank line that results from the \n being echoed by read but echo one in case of ...
3
votes
2answers
9k views

Bash/Korn shell script edited on Windows throws error '…^M: not found'

Some background on the issue: I am new to scripting and wrote a simple Bash script in Windows using Notepad++. cxStopAllServicesOnSERVER.sh #!/usr/bin/bash cd "/some/path" echo "Hi. Logs can be ...
3
votes
1answer
300 views

Display a right-click menu using a shell script

Is it possible to display a right-click menu using a shell script (or some kind of Unix command?) I'm trying to find a program that can be used to display a context menu at a specific location on the ...