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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0
votes
3answers
16 views

iterate lines containing zeros in bash

I am having a file which looks like this: 141.519 141.009 140.121 135.519 0 0 0 0 I'm writing a shell script and I want to replace all lines containing a zero with -1e+10. So far, I’ve tried this: ...
1
vote
2answers
29 views

Bash: issuing trap twice

I have a very simple question. I can't believe the Bash manpage doesn't explain this already, but anyway... If I issue the trap builtin twice [for the same signal], what happens? Is the second ...
1
vote
4answers
93 views

Replace string repeatedly

When I execute command sudo iwlist wlan0 scan | grep ESSID resulting ESSID:"DHS_3RD_FLOOR" ESSID:"MAXTA" ESSID:"MAXTA_5THWL" ESSID:"OPENSTACK" ESSID:"IOT" ESSID:"ved_opa" ESSID:"dlink" ...
2
votes
1answer
38 views

Execute command that was displayed on the screen as a message

A message is displayed many times on the screen after entering certain command. I need to retype the entire suggested command or copy and paste it. Is there a shortcut to do the same using the ...
0
votes
0answers
15 views

Get similar links from one site using wget [on hold]

I have a site (http://a-site.com) with many links like that. How can I use wget to crawl and grep all similar links to a file? <a href="/user/333333/follow_user" class="btn" ...
0
votes
1answer
35 views

.bash_history keeps truncating

My .bash_history keeps truncating even though I set: export HISTSIZE= export HISTFILESIZE= On my .bash_profile. Im not sure when it happens but it might happen when I logout or shut down my ...
0
votes
1answer
36 views

How to create a script to run several scripts on different servers

I need to automate the execution of several scripts, and I'm writing a script. The scripts have to run concurrently because they are part of a benchmarking suite. I'm trying to execute 6 different ...
1
vote
2answers
118 views

Can I hook into the cd command?

I'm trying to set something up on a server I run, when ever I cd into a public_html folder 95% of the time there's a few commands I will always run to check certain things. Is there anyway I can hook ...
5
votes
4answers
333 views

List the number of lines in files

How can I list the number of lines in the files in /group/book/four/word, sorted by the number of lines they contain? "ls -l" command lists them down but does not sort them
2
votes
0answers
12 views

Programatically / dynamically adjust SSH session port forwards

I have a workflow where I am trying to do the following: For a given existing SSH session, access the remote machinne and perform a process from which a port is returned (e.g. a remote daemon has ...
0
votes
1answer
11 views

Virtualbox vboxmanage clone does not show up in virtual machine list

I have a virtual machine that I am cloning with the command line interface to virtualbox like so: vboxmanage clonevm origVM --name origClone However, the clone is added to the directory ...
-1
votes
0answers
44 views

Scripting multi-volume (GNU) `tar` with pre-defined number of volumes

I've wrote me a little script to test (or extract) a very big multi-volume tar archive (note: created with GNU tar), each of which 00x.tar chunk will fit onto a standard DVD: #!/bin/bash d=$(dirname ...
1
vote
1answer
36 views

change a bash script while it is running [duplicate]

I have a script test #! /bin/bash sleep 60 echo hello I ran it by setting it executable and ./test, and while it was running the sleep command, I changed it to #! /bin/bash sleep 60 echo ...
2
votes
3answers
29 views

How to parse env variable in a quoted string?

I'm having a hard time getting the value of an environment variable ($GHREPO) in a quoted string. Here is the command I'm running. I'm trying to make a directory with the value of ...
3
votes
1answer
18 views

Bash scripts ran from from gnome/nautilus don't have enviroment variables

In my ~/.bashrc and ~/.profile I have some variables set to some filepaths: export MY_VAR1="/path/to/somewhere" In my ~/bin/ (which is added to my PATH) I have a few scripts that rely on those ...
1
vote
1answer
5 views

Virtualbox list vrde port for vm on commandline

I have a Virtualbox VM that is configured with VRDE for remote access using RDP. I'm familiar with how to set the vrde port, but for a given VM I have not found a way to query the current vrde port ...
1
vote
3answers
50 views

How to test for unknown commands in shell script?

I would like to know, if there is a way to go through a shell script and getting a warning for every command, that is unknown. I know bash -n for syntax checking, but it doesn't tell me, if there are ...
0
votes
1answer
19 views

Confusion about basic bashscript loop - until/done [duplicate]

I have a bash script I'm working on to help with an installer. why doesn't this work? function fn_myFunc(){ local MYVAR=0 until ["$MYVAR" -ne 0]; do whiptail --yesno ...
11
votes
3answers
266 views

Start a process on a different tty

After about an hour of Googling this, I can't believe nobody has actually asked this question before... So I've got a script running on TTY1. How do I make that script launch some arbitrary program ...
1
vote
0answers
5 views

Capturing data from a Fluke 1620a via Bash /dev/tcp file descriptor

I am currently trying to develop a script that will connect to a Fluke DewK 1620a Themo-Hygrometer and pull the current temperature and humidity readings from the device. While these devices have a ...
7
votes
3answers
409 views

in Bash, how to not include extra arguments in an alias?

I am trying to do something like alias ftp='echo do not use ftp. Use sftp instead.' just so that ftp will not be accidentally used. But I noticed that ftp abcd.com will cause the command to ...
-2
votes
0answers
33 views

making a delete script and a restore script

I'm looking to create two scripts; one to "delete" a script, and one to "restore" I need "del " where this will move the file located at to the dustbin directory in a way that will allow it to be ...
-1
votes
1answer
19 views

how to replace a specific pattern from all files [duplicate]

suppose I want to replace abc with xyz in all files in a directory. How do I write a script for this ?
2
votes
2answers
59 views

Update process name in shell, is it possible?

In C/C++ it is in general possible to do strcpy(argv[0], "new process name"). It's a hack used in malicous software to hide real process name. Is such operation possible via shell? What I want to do ...
2
votes
0answers
29 views

Programmatically get CPUs 'detailed' usage, like top/htop

htop has a great way to show CPU usage. It shows the activity (usage in %) of each cores, and each core gauge is divided into three parts : blue: low priority processes green: normal processes red: ...
4
votes
2answers
82 views

Using `case` to handle script arguments

Can I use the case statement to handle arguments? So, using -restart I'd like execute "-umount" and "-mount" #!/bin/bash case "$1" in -mount mount /ip/share1 /local/share1 ;; -umount umount ...
4
votes
8answers
552 views

Remove everything that is not a 4 character number

I need to remove everything that is not a 4 character number such as 9838, 6738, 1337 or 1889. I though that this command would work: sed 's/....[^0-9]//g' . Means any character in regex, and ...
0
votes
1answer
25 views

check status process output

I wanted to understand how to create a script sh that allows me to see if an additional script functions correctly. For now this is the script that I created. if /run.sh status echo "$SERVICEXE ...
1
vote
1answer
40 views

Difference between / and // [duplicate]

On the bash prompt one, three or more slashes (/,///,////, ...) are treated as a single slash, whereas two slashes (//) are left as is: 12:07 $ cd / 12:07 $ pwd / 12:07 $ cd // 12:07 $ pwd // 12:07 $ ...
1
vote
1answer
19 views

'hhighlighter' wrapper script saying command not found

I have gotten the wrapper script 'hhighlighter' from https://github.com/paoloantinori/hhighlighter which colors anything you want in stdout. I followed the instructions about installing ack-grep, ...
2
votes
1answer
23 views

Command Line Macros in Comments using SLURM

In my opinion, comments are comments are comments. They should NEVER change program state. Sadly, the people over at SLURM disagree. SLURM requires the following syntax (or something similar) to ...
0
votes
1answer
48 views

Bash script class path issue with java

jvm.script.sh /opt/scripts/jvm/jvm.script.sh #!/bin/bash JAVA_HOME='/java' PATH="$PATH:/$JAVA_HOME/bin" java -cp ./classes:./lib com.mystuff.bar.foo.myclass & init.script.sh ...
0
votes
3answers
66 views

How to print only certain characters?

I have to translate the permissions of a file this way: r ► c w ► s x ► e Then, I must extract the group of characters which are related to owner group. Last step is to print that group of ...
0
votes
2answers
55 views

Help in starting learning bash script [on hold]

I have just started analyzing sequencing data using Linux. I have created a pipeline for variant calling that includes eight commands or maybe more. I need to paste every command one by one and wait. ...
0
votes
1answer
53 views

Editing lines in a file using a bash script?

I am creating a bash script that installed VSFTPD / FTP. After the installation some configuration is required in the "/etc/vsftpd/vsftpd.conf" file. This includes making sure the following lines are ...
1
vote
2answers
68 views

Sort files according to their extensions

I have made a script that will sort files according to their extension and place them in the proper folder. For example, place abc.jpg in the directory jpg. #!/bin/bash #this script sorts files ...
0
votes
2answers
26 views

How do run MYSQL scripts from a shell script with bash variables?

Im making a script where I connect to a database, look for a value and then if that value returned something then I will do something else. ip=$("variable is defined here") Then I connect to the ...
3
votes
2answers
107 views

single quote within double quotes and the bash reference manual

In section 3.1.2.3 titled Double Quotes, the bash manual says: Enclosing characters in double quotes (‘"’) preserves the literal value of all characters within the quotes, with the exception ...
12
votes
2answers
789 views

How can variables use “~” for cd'ing?

How can I use a variable - $BASE in my cd. I tried the following but I get an error $ cd ~/z/repo_1_ruby_193/ 23:23:57 durrantm Castle2012 /home/durrantm/z/repo_1_ruby_193 $ BASE="~/z" 23:24:03 ...
0
votes
0answers
49 views

(Solved) Bash Graphical uninstaller using a tool to make graphical my script [on hold]

I have a problem with logic on this part of my script, I can't see my fault. . Basically the script must be do the follow: Well when i click "Yes" its "Yes" when i click "No" , its "Yes" , i dont ...
0
votes
0answers
17 views

Bypassing the security message in Debian 7 when creating a bash script? [duplicate]

I've created a bash script which involves the installation / update of wget. As a result there is also a message from Debian showing the following: wget (1.13.4-3+deb7u2) stable-security; ...
1
vote
2answers
39 views

Oneliner which prints groups and their numbers which start with a '1'?

I have to write an oneliner which print system groups and their identifiers, for all groups whose identifiers start with '1'. For example, the result of cat command on /etc/group is this: I must ...
0
votes
0answers
16 views

Should all other versions of BASH be uninstalled after patching with the latest version?

My system (slacko puppy 5.7) still tests positive for shellshock after installing the latest version available (bash-4.2.053) I see that old versions are still installed (bash4-4.41_spup and ...
1
vote
2answers
133 views

How to grep for something that's in an environment variable and has a forward slash?

I want to grep a file, and I want to get all the lines that have a certain environment variable (to be exact, $PWD). Of course, using just cat file | grep '/'$PWD'/' is not working, since $PWD ...
1
vote
0answers
27 views

Having problems running a script thats built up through the script [closed]

I am currently making a script that sets variables and then runs a script. Here is a bit of what it looks like: #!/bin/bash xml='<This,is,hidden,because,of,personal,information><Id>' ...
4
votes
5answers
172 views

Calling multiple bash scripts and running them in parallel, not in sequence

Suppose that I have three (or more) bash scripts: script1.sh, script2.sh, and script3.sh. I would like to call all three of these scripts and run them in parallel. One way to do this is to just ...
3
votes
5answers
75 views

How to show distinct directories on find?

I want to find all directories containing, for example, files named *.txt. but the output must not contain duplicates. How to do it?
1
vote
2answers
41 views

Why double ampersand chained conditions runs in background together the last one?

I have some conditions for some background job to run: condition-command && condition-command && background-job & The problem is: I want the conditions to block until the job ...
1
vote
1answer
24 views

Updating a bunch of Macs via SSH. Could use some help

all. I'm working on a script that'll be running from our Mac server, and it will (hopefully) update all of our Macs via Munki (repo is on the same server) and the built-in softwareupdate command. ...
4
votes
4answers
164 views

How to capture command line input into logfile and execute it at the same time?

Let's say I issue some commands on the command line: #capture what follows $ echo "foo" foo # don't capture $ echo "bing" bing # capture again $ echo "bar" bar How can I log commands selectively ...