Questions specific to GNU’s Bourne Again SHell, as opposed to other Bourne/POSIX shells. For questions about Unix shells in general, use the /shell tag instead.

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6
votes
1answer
42k views

unexpected EOF while looking for matching `"' - bash script

I just wrote a bash script (im a Newbie to shell-scripting ;) ) and always getting this EOF-Error. So here is my script (only works on OS X): #!/bin/bash #DEFINITIONS BEGIN en_sq() { echo -e "...
3
votes
4answers
12k views

“Can't cd to /home/user” when sourcing a script [duplicate]

I have this script: echo $HOME cd $HOME cd / cd /usr/local/src/ When I run it like this . script.sh I get this output: /home/user : No such file or directory : No such file or directory : No ...
2
votes
4answers
505 views

How to have service that makes sure program keeps running?

I made a service called thin_keep_alive_service in /etc/init.d. I gave it chmod +x rights. The script looks as follows: #!/bin/bash ### BEGIN INIT INFO # Provides: thin_keep_alive_service # ...
1
vote
2answers
251 views

Run command on startup for one user

I made a new user on my server. The user is not logged into the bash shell on startup. To do this I can run /bin/bash --login and it works. Where do I place this command so that it runs automatically?...
1
vote
2answers
470 views

Double click Linux Bash Script and debug with pause commands

I'm fairly good with windows .bat scripts and normally use the pause command while developing them so I can see things step by step as the script runs in the command prompt. I am trying to do ...
10
votes
4answers
819 views

Can I reference a command before '&&' after '&&'

Not sure how else to phrase the question, but basically, I often find myself running a command like vagrant to bring up the VM, and then ssh into it like below: vagrant up && vagrant ssh ...
3
votes
2answers
238 views

get result text from CLI command

I'm writing a bash script and I need to capture the text resulting from the output of the rsync command, for instance, the following command: rsync -av "$FOLDER1" "$FOLDER2" prints: ... sent 109,...
6
votes
2answers
742 views

how to mount a range of drives in bash?

I use something like this to unmount a range of drives: umount /dev/sd[c-k]2 Is there any way to use same thing with mount? something like this: mount /dev/sd[c-k]2 /[c2-k2]
9
votes
1answer
1k views

What is the keyboard shortcut opposite to Ctrl+k?

Ctrl + K deletes rest of line in an UNIX command line. How do I delete all the text before the cursor?
2
votes
2answers
590 views

grep works fine in command line but returns nothing in script

I'm trying to write a small script to get me list of files that match certain criteria into a file. #!/bin/sh cd /var/www_data/patch/ grep --include=\*.{php,ini,conf,sh} -ril -P "'([\d\w\-\_\.]+)(@...
2
votes
4answers
706 views

Modify bash arguments if only one argument is set

I created a script with the standard getopt magic, so you can call the script with batman-connect -c ffki How can I add an option to call this script with only one option without dash? batman-...
6
votes
2answers
435 views

echo of a string with an exclamation point

Here are what I put in bash and the results I got about 'echo': $ echo '!$' !$ $ echo "!$" echo "'!$'" '!$' I'd like to know how 'echo' deals with the second input. It seems to me that '...
1
vote
0answers
412 views

Cannot SSH after switching to Netgear router

I have Comcast Xfinity internet. When I was sent their Wifi router/Cable modem combo box, I was able to use SSH perfectly. However, since the Wifi from the box was weak, I decided to buy my own router:...
0
votes
0answers
293 views

Script to compare directories and move files (like rsync)

I use rsync to sync data between two servers. If I completely rebuild the directory structure, rsync cannot understand this and will attempt to recopy everything. I am aware that Unison is capable ...
4
votes
3answers
593 views

Automatically put an alias into ~/.bashrc or ~/.zshrc [duplicate]

Is there a command line util/script that automatically saves aliases? E.g. save-alias my-ip="curl ipecho.net/plain" and that will define an alias, then add/update it in ~/.bashrc or ~/.zshrc I was ...
2
votes
2answers
1k views

make `find` return with a non-zero exit code if error occured

Why am I seeing the following: $ find -not -exec bash -c 'foo' \; -quit bash: foo: command not found $ echo $? 0 This is a reduced version of the actual script I am using which I post at the end ...
6
votes
2answers
386 views

bash crashed with for loop [duplicate]

The question may be trivial but with this simple for loop for i in {1..10000000}; do echo "$i" line >> file done my shell crashed after some elaboration time (the tab in the terminal emulator ...
0
votes
2answers
67 views

arguments with pure command line

I don't know if this is possible with terminal command line rather than a script. I want to type a command which takes variables $0, $1 and enter the variables separately either at the start/end of ...
2
votes
2answers
105 views

How to make an infinitely executing command kill itself when certain conditions are met?

I'm running a command on command line which infinitely generates a certain data and I'm looking for a particular bit of data, so I used grep to find it. As soon as I get the data, I want the command ...
9
votes
2answers
639 views

Bash: process substitution and stdin

The following line is obvious: echo "bla" | foo | bar But does the ones below do the same? echo "bla" | bar <(foo) echo "bla" | bar < <(foo) Which of the foo and bar read "bla" from ...
0
votes
1answer
335 views

Haskell, C++, AWK, Bash, Lisp … Which one is faster? [closed]

I was wondering, which of these programming languages are faster at handling big data files of only strings: Haskell, C++(Boost), AWK, Bash, Lisp... So far I have found the paper Haskell vs. Ada ...
0
votes
1answer
386 views

How does sudo decide whether a command is only executable by sudoers with ALL rights?

I just wondered why on a Debian system with sudo installed a default user can execute ls but not ifconfig since the binaries do have the same rights: -rwxr-xr-x 1 root root 114032 Jan 26 2013 /bin/...
1
vote
1answer
201 views

Explanation for background tasks on bash

First, I write a simple PHP script <?php while(true) { echo 'hey'.PHP_EOL; sleep(1); } Then I run it like: php test.php & Obviously goes into background, but keeps running and ...
2
votes
3answers
155 views

When was the script started?

What I want is, -bash-3.2$ ps -aef | grep 29137 jeeadm 9794 1190 0 09:22 pts/2 00:00:00 grep 29137 jeeadm 29137 1 0 Sep02 ? 00:00:21 Java Second Row, Fifth Column entry, as in ...
3
votes
3answers
2k views

Determine maximum column length for every column in a simplified csv-file (one line per row)

To determine the maximum length of each column in a comma-separated csv-file I hacked together a bash-script. When I ran it on a linux system it produced the correct output, but I need it to run on OS ...
2
votes
1answer
2k views

How do I Nohup an interactive shell-script?

My Script is having 2 command-line arguments and then just couple of questions, after these questions the script will run for itself, I'm able to pass the command-line argument by just doing, -bash-3....
16
votes
3answers
2k views

why 'echo --help' doesn't give me help page of echo?

I tried 'man echo' in Bash and it told me that 'echo --help' will display help then exit, and similarly, that 'echo --version' will output version and exit. But why it doesn't work ? 'echo --help' ...
2
votes
1answer
171 views

create numbered files with defined content with bash

I want to create 69 files with a filename from 4006 through to 7075 and it each file needs to have some enumerated content, the following code prints on the shell what I would like to have inserted ...
5
votes
4answers
213 views

Count lines of non-terminating input

Is there any way to count the lines of a non-terminating input source? For example, I want to run the following for a period of time to count the number of requests: ngrep -W byline port 80 and dst ...
3
votes
3answers
81 views

environement variable assignment followed by command [duplicate]

What exactly is happening in the below bash incantation? x=10 echo $x I was under the impression that commands on bash can be chained using &&, || or ; but not simply separated by white-...
2
votes
2answers
7k views

Command not found problem in Linux-Ubuntu terminal

My friend is having problem in trying to call make to compile an application which both me and a second friend have previously successfully compiled. The file uses a "linux-devkit" pack that possess ...
10
votes
4answers
3k views

Alert when running process finishes

There are a few questions and answers on here with regard to being alerted when a process completes/exits(1, 2) – but these all assume that the user has issued said process themselves, and thus can ...
3
votes
1answer
91 views

Save lines to different files based on the date

How can I force a re-evaluation of this each time? cat > $(date '+%H-%M-%S').log So that when I first output something it gets written to one file, and after a few seconds I make another ouput ...
1
vote
1answer
2k views

Adding Text After Specific Line of File in Bash Script

I have a txt (ip.txt) file that contains IP addresess. I group them under TCP and UDP. File excerpt is below: #TCP 162.298.38.930 162.298.38.931 162.298.38.932 #UDP 162.298.38.930 162.298.38.931 162....
0
votes
1answer
4k views

Grep a string with spaces from a file

#!/bin/bash LIST=/errors_exception.txt cd /test for PATTERN in `cat $LIST` do for FILE in $(ls) do if zcat $FILE | grep -Fxq "$PATTERN"; then echo "$PATTERN found ...
0
votes
1answer
319 views

User input in linux bash to check against a list and respond with result

I am trying to get bash to ask for a user input from read and to check against a file or list of files, then respond with the result from that chesk. This is as far as I have gotten as of yet... read ...
1
vote
2answers
118 views

Difference in output from shell script

I am running a simple shell script which has a for loop and kicks off 16 threads in the back ground and waits for each of them to finish before moving on the next commands. Here is the shell: ...
1
vote
3answers
981 views

~/.inputrc file not sourcing correctly

I have this ~/.inputrc file that I created for certain key bindings. # mappings for Ctrl-left-arrow and Ctrl-right-arrow for word moving "\e[1;5C":forward-word "\e[1;5D":backward-word "\e[5C":forward-...
1
vote
2answers
111 views

Using sed with herestring (<<<) and read -a

I use sed with <<< and read to assign all words in a string to variables. What I do is: read -a A0 <<< $(sed '2q;d' /proc/stat) Hence, sed reads the second line of the file file ...
3
votes
2answers
884 views

Process substitution with input redirection

I am trying to understand input redirection in combination with process substituation. I am using bash 3 An example with tr is the following $ tr "o" "a" <(echo "Foo") tr: extra operand `/dev/fd/...
0
votes
1answer
788 views

How to set & retrieve a cookie via an executable bash script that is on the web

A simple bash script that can set a cookie when executed via web : #!/bin/bash echo "Set-Cookie: eee=1" echo "Content-type: text/html" echo "" echo "test" I replaced the entire codes above with the ...
-1
votes
2answers
196 views

Searching out a pattern from Logs

The format of the logs is in this manner: Junk Junk Junk : Junk Junk Junk:IP/Port Junk Junk I want to search using the IP and the output should be only the IP/Port part of each line in that log ...
1
vote
1answer
76 views

PID of process causing error

I have this script: #!/bin/bash # -> dump.$pid ulimit -c unlimited # trap ERR set -o errexit # also trap error in the middle of a pipe (1) # otherwise it will only trap the error on (2) set -o ...
0
votes
1answer
2k views

How to start several jobs in different screen sessions in a Bash-script?

The programm I want use can be started via ./myprogram < input_part1.txt > output_part1.txt How can I start four jobs of myporgram in a BASH-script where each job runs in a separate SCREEN-...
0
votes
1answer
444 views

Alias for finding a file not working in bash

The following alias for finding a file works in tcsh but not in bash. alias ff "find . -name '*\!{*}*' -ls" When I put the above line in .bashrc and then source it I get : bash-3.2$ source ....
3
votes
3answers
598 views

Finding groups of IP addresses in a file

I have a file with groups of IP addresses. The file looks like this: London: 1.1.1.0-1.1.1.200 172.25.2.0-172.25.2.100 Germany: 2.2.2.0-2.2.2.100 192.168.1.0-192.168.1.200 172.25.2.0-172.25.2.200 ...
10
votes
2answers
1k views

How to start XTerm with prompt at the bottom?

When starting XTerm the prompt starts at the first line of the terminal. When running commands the prompt moves down until it reaches the bottom, and from then on it stays there (not even Shift-Page ...
1
vote
1answer
204 views

Global variable for every script

I want to declare a variable in such way that every script can access and alter its value. I have written a script that set the value of a variable called flag on exit and I am using a crontab entry ...
1
vote
1answer
300 views

apt-get update: How to check for GPG errors when using scripts?

When running. sudo apt-get update For example something like this could happen. W: GPG error: http://deb.torproject.org wheezy Release: The following signatures were invalid: KEYEXPIRED 1409325681 ...
2
votes
1answer
502 views

How to print a bash variable that has an array as value

I wrote a script for my dwm statusbar. One part of it is finding the current cpu usage for every single core on my system. I figured out a way myself but I would need some help fixing a bug in this. ...