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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19
votes
3answers
969 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 ...
3
votes
1answer
574 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
2
votes
3answers
3k 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
5k 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
5k 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
521 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 ...
3
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
3k 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
191 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
161 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
836 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
1k 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
157 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
130 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
635 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
185 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 ...
10
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
398 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
12k 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
367 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 ...
2
votes
1answer
142 views

bash prompt with abbreviated current director including dot files?

I have the following in my .bash_profile (from a similar question here: PROMPT_COMMAND='pwd2=$(sed "s:\([^/]\)[^/]*/:\1/:g" <<<$PWD)' PS1='\u@\h:$pwd2\$ ' However, if the current directory ...
2
votes
1answer
252 views

How to make a permanent variable

In terminal: VAR="Extremely long and often used command" echo $VAR Output: Extremely long and often used command So far it works fine, but after restarting a terminal my variable doesn't ...
4
votes
2answers
1k views

Cygwin: readline lib loaded in different locations

Within cygwin, almost each unix command I type prints a warning message, takes time and eventually gives a correct result: -bash-4.1$ ls 0 [main] bash 7468 child_info_fork::abort: cygreadline7.dll: ...
6
votes
2answers
2k views

Pipe Password to Application When Asked

The following should be done in a bash script: curl --digest --user schmijos https://bitbucket.org/u/p/get/tip.zip -o tip.zip How can I automatically submit a password to curl when it asks for it? ...
14
votes
1answer
1k views

Command line utility to retrieve password, that has no echo back

Bash builtin read command doesn't seem to support it, now I need to let user input a password while no echo should be displayed, what tool can I use?
0
votes
1answer
554 views

Xmodmap on bashrc not working [duplicate]

Possible Duplicate: Why won’t my xmodmap command run on startup/login? I have my .bashrc file with the three following commands: xmodmap ~/.xmodmap synclient TapButton2=2 synclient ...
5
votes
2answers
297 views

Why arguments in braces do not expand in this case?

For example, I want to put some file names inside braces for expansion like this: $ ls blue_texture blue_waves green_light $ ls -m | tr -d ' \n' blue_texture,blue_waves,green_light $ echo ...
3
votes
1answer
59 views

How to determine the current Enhanced Zoom factor in Compiz?

When I use Skype :( need to, rather than want to ), I find that I sometimes want to open the main menu, but it doesn't have a shortcut key assigned to it (well, not one that I can find). I have ...
2
votes
2answers
3k views

How to deal with end of options — in getopts

I use getopts to parse arguments in bash scripts as while getopts ":hd:" opt; do case $opt in d ) echo "directory = $OPTARG"; mydir="$OPTARG"; shift $((OPTIND-1)); OPTIND=1 ;; h ) helptext ...
3
votes
2answers
5k views

How to loop through each file in FTP directory using a bash script [duplicate]

Possible Duplicate: How to delete the oldest file over FTP using CURL? I need to connect to a remote server using a bash script and then delete all files within the directory that are older ...
28
votes
1answer
9k views

Make cd follow symbolic links

I have my code mounted as an sshfs in my home directory, but the hierarchy is difficult to remember, so I created a symlink in my home directory leading to that directory. Is there a way so that when ...
1
vote
1answer
138 views

How can I have cd show the directory it switches into?

I have made my command prompt ($PS1) to be just username.../current_directory (using the 3 dots because my directory structure has lots of levels and they were taking up too much of the command line ...
2
votes
2answers
140 views

Parameter splitting

I have a bash script that is a simple wrapper around another process: $ cat ~/bin/s3cmd #!/bin/sh trickle -u 80 ~/bin/s3cmd.py $* $ This works great when the parameters don't contain spaces. ...
7
votes
3answers
3k views

bash - can I do : find … -exec this && that?

Is there a way to logically combine two shell commands that are invoked with find - exec? For instance to print out all the .csv files that contain the string foo together with its occurrence I would ...
3
votes
2answers
622 views

Limit stdout from a continuously running process

I haven't had much luck finding an answer to my problem, but maybe I'm not asking for it correctly. I have a process I startup like the following: nohup ping 127.0.0.1 > log.txt >2>&1 & ...
5
votes
3answers
901 views

Run ssh login command without modifying remote .bashrc

We have a bunch of servers set up with set -o vi in their ~/.bashrc. It would be nice to be able to ssh into these boxes and automagically run set -o emacs as a timesave. I've seen a solution ...
0
votes
1answer
158 views

Can Bash Emacs shortcuts be enabled over SSH?

I find Bash keyboard shortcuts such as Ctrl-a (jump to start of line), Ctrl-k (cut text following caret), Ctrl-n/Ctrl-p (next/previous line in command history) immeasurably useful in day-to-day CLI ...
12
votes
4answers
8k views

How can I kill and wait for background processes to finish in a shell script when I Ctrl+C it?

I'm trying to set up a shell script so that it runs background processes, and when I Ctrlc the shell script, it kills the children, then exits. The best that I've managed to come up with is this. It ...
1
vote
2answers
396 views

Easiest way to find/replace in a file using a list?

I have a file, foo.txt, and a regexp I want to find in that file. Each time I find the regexp, I want to take a line from another file, bar.txt, and substitute it in for the regexp match I found in ...
2
votes
2answers
3k views

Why does this “while read” work in a terminal, but not in a shell script?

I ran into this interesting issue while populating my WM bar with info text, which is applied by setting the root window's title, i.e. xsetroot -name "clever words" To this end, printing a fortune ...
7
votes
2answers
3k views

Create bash completion script to autocomplete paths after is-equal sign?

I want to create a bash completion script which recognises arguments of the form --arg and --some-arg=file. After reading this tutorial and some examples in /usr/share/bash_completion/completions/, ...
2
votes
2answers
1k views

How do I find corrupted archive files?

I have a lot of zip files. Some are not downloaded correctly and are corrupted. I want to remove them. Is there a way to find the corrupted archives in bash?
2
votes
2answers
990 views

Lost ls directory highlighting after a crash

Normally commands such as ls and grep offer nice syntax highlighting for me. But my system crashed (running an ubuntu VM) and after I restarted, I no longer have this highlighting, it's all a dreary ...
23
votes
2answers
8k views

In bash, is it possible to use an integer variable in the loop control of a for loop?

I have the following bash script: #!/bin/bash upperlim=10 for i in {0..10} do echo $i done for i in {0..$upperlim} do echo $i done The first for loop (without the variable upperlim in the loop ...
2
votes
1answer
3k views

find and globbing (and wildcards)

I tried finding some files (*.e*) that are in the same directory as another file (md.tpr). I needed to list them (for further processing) using the following: find . -name md.tpr -execdir ls *.e* \; ...
3
votes
5answers
3k views

Output multiple files from a single grep?

I'm not very experienced in shell scripting, but I'm trying to understand how to grep for a pattern and for each file where there is a match write a file to disk that contains the matched line from ...