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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1
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1answer
39 views

Can I start a background process with a specific working directory?

Say I have this structure /masterscript /a/script1 /a/b/script2 In masterscript I spawn the other scripts as background processes: "/a/script1" & "/a/b/script2" & The problem is that ...
4
votes
3answers
399 views

Why can't I `tail -f /proc/$pid/fd/1`?

I wrote a simple script which echo-es its PID: #/bin/bash while true; do echo $$; sleep 0.5; done I'm running said script (it says 3844 over and over) in one terminal and trying to tail ...
0
votes
1answer
51 views

Running shell script on cluster in parralel

I thought dsh(Distributed Shel) will be a good option but when i ran my shell script across my nodes, I didnt get expected output, dsh -aM -c bash /home/cloudera/bash_script.sh server2@x.x.x.110: ...
2
votes
3answers
103 views

bashrc in custom folder [duplicate]

I want to cleanup my home folder and have managed to move out most of the configuration files to the .config folder. But, one file I'm not able to figure out is the .bashrc file. How can I specify ...
0
votes
0answers
35 views

bash script to verify rhel patching

we have several redhat servers which we patch from redhat satellite. To avoid confusion, I'll use the term "host" to denote the server which is being patched. We have a script, say, patch.sh, which ...
2
votes
1answer
40 views

Bash: How to get different color for the command line and its output? [duplicate]

Basically, I am trying to edit my .bashrc such that when I type ls or whatever I type on the console, it will be displayed in Green color. At the same time, all the results / output displayed by ls or ...
0
votes
1answer
44 views

What does bash -l do and why can't it find ssh?

I have GitBash installed in a windows 7 box and I'm trying to figure out why running: bash -l ssh results in Welcome to Git (version 1.9.0-preview20140217) Run 'git help git' to display the help ...
1
vote
0answers
57 views

How to start a process chain from the shell

Is it possible and if so how do I: Start a /bin/bash process that is not bound to a terminal from a terminal? Hence, a shell process that shows up in the process tree as init -- bash. (Shells ...
6
votes
2answers
284 views

Why does source give an error “cannot execute binary file”

I have small file that does initialize a tmux session and then creates some windows. After some debugging and tweaking things worked fine until I renamed the text file (with the tmux commands) from ...
6
votes
2answers
188 views

Bash string concatenation used to build parameter list

Given this piece of bash: PARMS='-rvu' PARMS+=" --delete --exclude='.git'" echo $PARMS rsync ${PARMS} . ${TARGET} The echo shows the PARMS string as expected, no error is displayed, but rsync ...
1
vote
2answers
97 views

I want to suppress “no access to tty” error message?

I have a bash script where I use ssh to connect to another server and run some commands there. I found some sites that the error (Warning: no access to tty (Bad file descriptor). Thus no job control ...
3
votes
1answer
52 views

Suppressing “sudo: sorry, a password is required to run sudo” [closed]

I am trying to test if a user has the required sudo rights to run a command as another user without providing a password. What I have is this sudo -u other-user -n true if [ $? -ne 0 ]; then ...
0
votes
1answer
37 views

Bash STDERR still appearing after redirection [closed]

I am trying to parse the output of yum check-update in Bash 4 (Red Hat) and want to skip the first line that states: 'This system is not registered to Red Hat Subscription Management. You can use ...
3
votes
1answer
28 views

Bash ignoring my PATH and it's cache

I have installed pip in my ~/.local/bin/ directory. Here are the outputs of which, type and $PATH $ type pip pip is hashed (/home/bcc/pedros/.local/bin/pip) $ which pip /usr/bin/pip $ echo $PATH ...
1
vote
2answers
55 views

How to combine arithmetic expansion and brace expansion? [duplicate]

Can peoples combine arithmetic expansion and brace expansion? $ for i in {$((1 + 1))..5}; do echo $i; done; {2..5} $ echo "bash laughs at me"
4
votes
1answer
114 views

`seq` and bash brace expansion failing

IINM my system is failing when bashing for i in {0..10000000}; # Seven zeroes. do false; done # `bash` exited and its `tmux` pane/window was closed. or for i in $(seq 0 10000000); # ...
3
votes
2answers
100 views

Bash -c with positional parameters

Usually, $0 in a script is set to the name of the script, or to whatever it was invoked as (including the path). However, if I use bash with the -c option, $0 is set to the first of the arguments ...
2
votes
2answers
48 views

How to make bash script ask you if you want to execute the next segment(part)?

Soon as I execute the bash script. Given that I have set -x I will visually observe what is happening. But at certain parts, I want it to stop and ask me if I still want to continue executing the ...
4
votes
1answer
65 views

Bash script for scp interpreting tilde (~) too soon

So, I just started a new C++ class that requires me to program in a Linux environment. I don't have Linux installed on my machine, but I do have OS X and I can ssh into a linux machine in the lab at ...
0
votes
2answers
23 views

is there a way to escape a process in bash with out quitting it? [duplicate]

For example, I type sudo apt-get update and then a long list of stuff will come up for minutes.. if I want to escape from seeing this tiresome updating and take control of bash command line ...
1
vote
3answers
109 views

How to do command-line completion with files and folders

As a new Linux user, one of the things that's kept me away from the Command Line (CL) is that, for tasks involving files and folders (i.e. everything!), the amount of typing involved makes using the ...
1
vote
0answers
25 views

Bash tab completion fails inside of command substitution

I've been using kill $(pidof ) to terminate programs for a while, and since last night, every time I try to use tab completion inside the $() it throws an error, bash: unexpected EOF while looking ...
1
vote
2answers
40 views

profile.d on headless server

Is it a bad idea to put variables needed by a daemon program running at boot on a headless system in /etc/profile.d/? From my understanding profile.d doesn't get executed until someone logs into the ...
3
votes
1answer
126 views

Set Ubuntu System Proxy Settings without Restart from commandline

I am using Ubuntu 14.04 . I want to change the http proxy settings from the command line. This should be equivalent to changing in the GUI(All Settings->Network->Network Proxy) and clicking the button ...
1
vote
2answers
36 views

Restarting a service from a script

I have a init script - /etc/init.d/myservice, which starts some processes, including a CLI process. And from this CLI process, I am adding a command which can be used to restart the service (restart ...
2
votes
1answer
108 views

Sort the 'last' output by month

I know that the command last | tac is enough, but I want to do it using the sort command. I cannot sort it by column, it always sorts the first one only. Using bash on Arch Linux.
2
votes
2answers
86 views

find file, copy but with different name

I have files with random numbers in /home/user/files folder (every 4 days I have new ones). for example: john20 john25 john40 tom12 tom32 simon2 simon8 simon53 I want to take only last modified ...
0
votes
0answers
40 views

Is there any suggestion to my bash script that (un)mounts an ISO file in order to make it better and safer?

I am new to bash script, and I wrote a script to mount / umount an iso file by detecting whether the /media/iso-file-name exists. Is there any suggestion for the script as below in order to make it ...
1
vote
2answers
35 views

Find out which process is in foreground on bash

I have a bash session open for which I have the PID, although I am not in control of the terminal (e.g. could be another user). This bash session has spawned some child processes. Is there any way to ...
2
votes
1answer
26 views

How to get clicked-on filename as argument of shell script triggered by this mouse-click

If, in Ubuntu's Nautilus, I click a midi-file, a window opens to specify an application for processing the file. Another option is a "user generated command" (UGC). (Let me choose Ubuntu, Nautilus, ...
2
votes
3answers
59 views

at job seems to be running using /bin/sh though I have a #!/bin/bash

I am trying to run a job using at, and I have a bash script (I do have #!/bin/bash as the first line), but the job fails because of use of [[ and ]] in the script, I see the following in the mail that ...
2
votes
3answers
149 views

Saving individual output lines into variables

I'm using find -mtime -2 to find files modified in the past 24 hours or less. The output looks like this. /home/user/logs/file-2014-08-22.log /home/user/logs/file-2014-08-23.log I need to save the ...
1
vote
1answer
45 views

Copy newest file in directory over SSH

How might one copy the newest text file from a particular directory on a remote server to his local machine? On the server itself I can do the following: $ cat `cd /home/user/dir ; readlink -f $(ls ...
2
votes
2answers
117 views

Why does Bash's “source” command behave differently when called from a function?

Given the following sourceable bar Bash script ... echo :$#:"$@": ... and the following executable foo Bash script: echo -n source bar: source bar echo -n source bar foo: source bar foo function ...
1
vote
1answer
84 views

How does bash execute an ELF file?

When I'm on my Linux Box I use bash as a shell. Now I wondered how bash handles the execution of an ELF file, that is when I type ./program and program is an ELF file. I grepped the bash-4.3.tar.gz, ...
2
votes
1answer
230 views

Running sh script: «Permission denied» despite the executable bit and root rights

I installed Debian in VirtualBox (for various experiments which usually broke my system) and tried to launch the VirtualBox guest addon script. I logged in as root and tried to launch autorun.sh, but ...
6
votes
1answer
81 views

Getting wrong $LINENO for a trapped function

I am writing a Bash script for myself to learn scripting. At some point, I need to add trap in order to clean unwanted directories and files if script is killed. However, for some reason I do not ...
2
votes
3answers
98 views

Script to ssh and run a command doesn't work

Below is the script. I wanted to login several servers and check for the kernel version. #!/bin/bash #input server names line by line in server.txt cat server.txt | while read line do sshpass -p ...
2
votes
1answer
23 views

ionCube shell script gives error

I have this shell script to install ionCube loader: if [[ $(id -u) -ne 0 ]] ; then echo "Please run as root" ; exit 1 ; fi echo "Welcome to this script to install the ionCube loader on CentOS!" cd ...
6
votes
0answers
152 views

Echo difference between Ubuntu and Red Hat

I have mostly been experimenting with Ubuntu but recently was using a Red Hat Enterprise system and was surprised at a difference I found setting and displaying environment variables. In Ubuntu I ...
5
votes
1answer
25 views

Upstart and bash function names containing “-”

I inherited some bash scripts where the author used "-" in the function names instead of the more normal "_" e.g.: function a-b { ... } Ugly but legal in bash. Problem is I sourced this inside an ...
2
votes
3answers
63 views

Checking if an input number is an integer

I'm trying to check if an input is an integer and I've gone over it a hundred times but don't see the error in this. Alas it does not work, it triggers the if statement for all inputs ...
3
votes
5answers
162 views

efficient cross-os file size shell function

I'm looking for a simpler way to have a cross-os-unix file size check. I could use wc -c but I'm concerned the performance may suck on large files (I'm assuming it just counts chars and doesn't do a ...
1
vote
3answers
118 views

Calling a function which calls another function with a for loop

I am calling a function with a for loop and saving the returned value to a variable. When I run the code, I get a command not found error. What is wrong? #!/bin/bash check_1() { x_$1=$(check_2 ...
0
votes
2answers
38 views

how to pass a value to a variable that in a other variable

I am new to scripting. I am getting a "bad substitution" error while running this code. I want to print the values in h_1, h_2, h_3with a for loop. #/!/bin/bash h_1=12 h_2=13 h_3=14 for ((i=1; ...
3
votes
1answer
180 views

How do I fill my password automatically from .bash_profile when running command as sudo?

I know I could just put something like sudo mypassword in my .bash_profile, but I don't want to run every command as root. I want password to autofill under following circumstances: only the ...
3
votes
1answer
37 views

Error when calling a script from inside another script

I'm writing a couple of scripts to start vlc and periodically update its playlist. The update_pls.sh works well if I execute it from prompt, but when I call it from start_vlc.sh, in each for cycle I ...
-1
votes
0answers
35 views

Become root after login via plink from Windows host

I m trying to connect to a linux server from Windows host via plink. I couldnt figure out how to become root after logon. I have to login with ordinary user first as I can't change config of the ...
4
votes
3answers
71 views

How do I gracefully suspend and resume `cmd1 && cmd2 && cmd3` chain?

From the previous question it seems I failed to understand how && and ^Z interact properly: $ command1 && command2 && command3 Running command1 ... Running command2 ...^Z [1]+ ...
1
vote
2answers
80 views

aliasing a slightly complex script on Linux/bash

Stormvirux provided this nice script in another thread. It puts column headings on the output of an ls -l listing: #!/bin/bash { echo Permissions links Owner Group Size Last_modMonth Last_modTime ...