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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2
votes
1answer
115 views

How to read variables from a php file in bash

How do I export variables from a PHP script in Bash? I'm writing a Bash script to read database names from config.php files of each website, and then import the database from the backup repository. I ...
3
votes
1answer
36 views

How do I turn off redirection once I've turned it on? [duplicate]

I found a great solution at Redirect all subsequent commands' stderr using exec. I used the example: exec > >(tee $somelog) 2>&1 ...and managed to get everything to tee great. ...
4
votes
3answers
61 views

Force POSIX mode

Brace Expansion, eg {a,b,c} is not defined by POSIX. I would like to run my shell in POSIX mode. With Debian this is simple enough: $ bash -c 'echo {a,b,c}' a b c $ sh -c 'echo {a,b,c}' {a,b,c} ...
1
vote
1answer
43 views

script Multiple Commands

I have a PHP script I'm running from Cron. I want to save its output to file, but also want to save the shell output to a different file. Ideally, I'd like to have this in one line. As such, I tried ...
0
votes
0answers
18 views

Can I make history not print any timestamps for commands that were run before I enabled that option?

If you run history, it outputs the current date before commands that were run before I enabled timestamps, is there anyway I can make it ignore that? For example, if my .bash_history looks like this: ...
-1
votes
2answers
38 views

Grep expression with spaces - BASH

I would like to grep ACCEPT, DROP, REJECT as is shown below. -P INPUT ACCEPT -P OUTPUT DROP -P FORWARD REJECT I executed iptables -S | grep -E '\-P INPUT|\-P OUTPUT|\-P FORWARD' | awk '{print $2}' ...
1
vote
2answers
29 views

BASH - Associative array - getting the value of the key in the final element

I have created an associative array as follows: declare -A test_array test_array[0,0]="1" test_array[0,1]="A" test_array[0,2]="11" test_array[0,3]="AA" test_array[1,0]="2" test_array[1,1]="B" ...
0
votes
1answer
31 views

Why not display characters which I typed in tty? [duplicate]

I pressed CtrlAltF1 to enter TTY1. I worked a while mainly on vim, then my shell (bash) stops echoing. If I type echo abc it does not get display. Instead I get a screen like this: How do I fix ...
5
votes
3answers
1k views

Why does Ctrl+Arrow make my terminal switch to a strange mode?

When i type Ctrl+Left or Ctrl+Right within Guake or gnome-terminal the last one's behaviour turns to a some kind of non-usual mode: - key acts like arrow up and + like arrow down, v runs Nano, etc. ...
0
votes
2answers
256 views

Double quotes in bash

I am trying to create a bash file which calls a program that expects a parameter to submitted between two double quotes. Take a look at my file content. #!/bin/bash echo ./yowsup/yowsup-cli demos ...
3
votes
2answers
53 views

Getting the full path name of a given directory

Suppose I'm in /path/to/dir. Within this dir is another dir called subdir. Is there a command I can issue which outputs the full path to subdir, no matter how it is identified? For example: $ cmd ...
1
vote
0answers
29 views

Bash one liner not looping [duplicate]

I am trying to loop through a file to run commands remotely via SSH but its only sending the first command and stopping. while read a b c; do ssh root@$remoteserverip "/usr/bin/mysql -e \"grant all ...
1
vote
0answers
13 views

Trap error on remote server

I have a script that run commands locally, and also execute commands on a remote server via SSH. When an error occurs on the local server, I am able to trap it, send an email and exit the script. But ...
0
votes
1answer
29 views

Why does piping filenames into VIM break bash when I return to the shell?

I searched for a few files with find and I wanted to open all of them in tabs in Vim. So I tried this: find . | xargs fgrep -l myExpression | xargs vim -p This worked great, except when I was done ...
1
vote
2answers
47 views

Add columns to a text file with set spacing in Bash

I am setting up a malware zone file in DNS which will point all hosts to a specific IP. The file is simply a list of hostnames. This is what I have now: googlle.in ...
-1
votes
5answers
80 views

Bash script to insert letter based files into directories [closed]

I'll start by saying I'm a complete novice to this. So basically, what I need to do is create a script that makes 15 directories (named from 1 to 15) and inside each directory I have to have a letter ...
1
vote
1answer
31 views

echoing a value from a BASH function after a command has been run in the background

I am trying to run the following, as a test for something else: function echo_test { sleep 60 & > /dev/null returnpid=$! echo $returnpid } pidthatwasreturned=$(echo_test) echo "This ...
6
votes
2answers
392 views
0
votes
2answers
37 views

Bash Script execute command as user

I'm just wondering if it's possible to execute a command inside a bash script as a specified user and supply the password in one string. At the moment I have COMMAND="${DIRECTORY}/script.sh" su -c ...
3
votes
3answers
629 views

read only TMOUT variable – workaround to disable automatically exit shell when there is no activity

We have here a read only Bash variable. I am not allowed to unset that variable. $ echo $TMOUT 1800 As a workaround I wrote those lines (that my session don't exit) #!/usr/bin/perl $|++; while ...
1
vote
1answer
15 views

alternative approach for selective deletes from rsnapshot tree with find?

I'm looking for a generalizable solution to this problem, 'cause I'm sure it will come up again. I have a client that does medical research. Periodically we have to remove the datasets provided by ...
1
vote
2answers
33 views

Is there any command that mimics the double tab list in bash? [duplicate]

I would like to get the same possible autocomplete list as hitting [Tab][Tab] in bash but with a command. Is there anyway to do that?
0
votes
0answers
15 views

Setting anacron on mac

I set cron to run script every day using env EDITOR=nano crontab -e where I wrote something like this @daily path/to/sript.script Now I want to use anacron to be sure that script is going to be run ...
0
votes
1answer
33 views

Simple if/else statement not working [duplicate]

I have been trying for a long time to get this basic bit of code to work in a shell script, but to no avail, the code doesn't work! read dec if [ dec="Y"]||[dec="Y"]||[dec="y" ]; then let repeat=1; ...
0
votes
2answers
41 views

Echo a string with a variable in it without expanding/evaluating it [closed]

I've searched everywhere. Tried echo and print. Tried single and double quotes. But I have parsed data and assigned it to a variable and would like to then evaluate it for if there is a variable ...
1
vote
0answers
20 views

Bash tab completion not working within symlinked directory

I'm working with Bash 4.2.46 on RHEL7 with the bash-completion packages installed, but I seem to have found an odd corner case where tab completion doesn't seem to work as expected. I have a set of ...
-1
votes
0answers
27 views

dump non formated output of commands to csv file

I have some commands with which i can get list of VMs running on hypervisors. I redirect that output to some file.txt and use while loop to read each line from file.txt and execute two more commands ...
1
vote
2answers
43 views

How to define alias for non interactive/non login shell?

I have a user (zabbix) with shell set to /sbin/nologin. The user's home is /var/lib/zabbix and I inserted alias curl='curl -k' into ~zabbix/.bashrc. However it does not work when I (for testing ...
13
votes
6answers
392 views

Use system command instead of Bash builtin without specifying the full path

I use Bash as my interactive shell and I was wondering if there was an easy way to get Bash to run a system command instead of a shell builtin command in the case where they both share the same name. ...
1
vote
1answer
154 views

How to change a pom.xml version with linux shell script

i have a pom.xml contain a line <version>x.y.z-tag</version> where tag could be: snapshot, alpha, beta or release. and x.y.z is a number version like: 1.0.0 or 1.2.1 .... i want to ...
1
vote
1answer
40 views

if condition in bash scripting

I have a text file that I want to check some line as below com1=`awk 'NF{a=b;b=$0} END{print (b ~ /\com/)? "Yes" : "No"}' $myfile` com2=`awk 'NF{a=b;b=$0} END{print (b ~ /\t/)? "Yes" : ...
2
votes
2answers
346 views

Cannot rm file: Disk quota exceeded

In bash (and over ssh) running rm FILENAME gives the error: rm: cannot remove 'FILENAME': Disk quota exceeded. I've seen the other posts (and everyting down the first page of google) on this topic and ...
0
votes
2answers
41 views

command not found error after giving permission to access file using chmod

I've been trying to run a script using chmod. Here's how I tried to execute the script: $ chmod u+x tester $ ./tester ./tester: Command not found. I always get the Command not found error and I'm ...
5
votes
1answer
9k views

Kill all background jobs

Is there a more compact form of killing background jobs than: for i in {1..5}; do kill %$i; done Also, {1..5} obviously has a hard-coded magic number in it, how can I make it "N" with N being the ...
1
vote
2answers
38 views

Recover from faking /proc/meminfo

So, without really thinking too much, I ran this script: #!/bin/bash SWAP="${1:-512}" NEW="$[SWAP*1024]"; TEMP="${NEW//?/ }"; OLD="${TEMP:1}0" sed "/^Swap\(Total\|Free\):/s,$OLD,$NEW," /proc/meminfo ...
0
votes
0answers
34 views

Does RPM automatically retry failed download attempts?

My particular situation isn't on a Linux box, rather an IBM i. But I'm running RPM within a BASH shell and attempted to download and install nano using RPM - it failed. I didn't think anything of ...
-1
votes
1answer
37 views

Replace duplicate rows by one column [duplicate]

I have a file in the below format. [ I tried using awk and sed in all the possible ways which i am aware of but couldn't find a way to reformat the file in the format which i am looking for. I would ...
2
votes
2answers
907 views

Any way in Bash to write to a file every X seconds without closing it?

The hardware watchdog on my system needs a 0 written to /dev/watchdog at less than 60 seconds interval or it will fire. The file handle must be kept open however or the watchdog is then disabled. ...
0
votes
1answer
18 views

get command line agrument by variable in shell script

I want to get the arg of a command from a var that has the index in it of the arg that I want. Something like this # command in terminal, `foo -r -f value_wanted` index="3" var=$"$index" echo $var ...
3
votes
2answers
961 views

How to count occurrences of all the words in all the files of a directory using grep? But with count incremented only once per word per file

I have already asked a similar question but people misunderstood what i was asking. I was asking how to generate a list of every word with a word count incremented only once per word per file. For ...
0
votes
3answers
50 views

piping with grep

I want to search "C" in the grades column inside the file "input.csv": roll,name,total,rank,grade 001,A B,78,23,C 003,F YZ,100,1,* and what I'm trying is: cut -d"," -f4 input.csv | grep "C" ...
4
votes
1answer
66 views

Why is subshell created by background control operator (&) not displayed under pstree

I understand that when I run exit it terminates my current shell because exit command run in the same shell. I also understand that when I run exit & then original shell will not terminate because ...
27
votes
5answers
64k views

How to measure time of program execution and store that inside a variable

In order to find out how long certain operations within a Bash (v4+) script take, I would like to parse the output from the time command "separately" and (ultimately) capture it within a Bash variable ...
0
votes
0answers
39 views

Pg_dump does not work in Cron

I have the command below and run it succesfully: /usr/lib/postgresql/9.1/bin/pg_dump -U dspace --format=c --file=/dspacebkp/dspace_db_$(/bin/date +\%m\%d\%Y)_uncompressed dspace I can see my new ...
3
votes
2answers
62 views

How does the -d option to bash read work?

I have a bash script where I'm trying to assign a heredoc string to a variable using read, and it only works if I use read with the -d '' option, i.e. read -d '' <variable> script block ...
0
votes
0answers
15 views

How to edit $PATH? [duplicate]

After searching, I can't still figure out how to edit $PATH. Now its value is: ...
0
votes
1answer
16 views

bash: /home/hadoopuser/hadoop/sbin: Is a directory

I am in Ubuntu 14.04 LTS. Based on how to set a Hadoop cluster I am executing this: # Add Hadoop bin and sbin directory to PATH export PATH=$PATH:$HADOOP_HOME/bin;$HADOOP_HOME/sbin where I know ...
2
votes
1answer
32 views

Automatically add slash when navigating through symlink

I use symlinks a lot and pretty much linked my whole home directory into a folder .other or .dotfiles. When I'm im my home directory and try to got into the folder .config/, its actually a symbolic ...
2
votes
4answers
52 views

Change dir from script without a “shell procedure” or “sourcing the script”

I know what I can make a shell procedure or source the script instead of running it to cd the shell I am using. What I want to know is there any way to cd the "parent shell" (not sure if that is the ...
0
votes
0answers
17 views

lftp — continue behavior?

I have a straight forward use case that I thougth lftp could do with the --continue flag - alas it didnt work. Is it doable? - Am I missing some flags, and are there any easier way to do this with ...