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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1
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0answers
111 views

export -f in .bashrc after upgrade to bash 4.3.30 kills builtins?

I recently upgraded my bash (Mac OS X 10.6.8) from 3.2.48(1) to 4.3.30(1) via macports, and while the install seems to have gone smoothly, the two spots in my ~/.bashrc where I had export -f myfunc; ...
0
votes
1answer
339 views

Can call login command from terminal

I want to create a user using useradd from root in my terminal window, after it I call passwd to set user's password. So I cant call login username because when I call it from terminal it closes ...
0
votes
1answer
278 views

generate password that is random length between 8 - 16 ( i have the generator but its not dynamic) [duplicate]

This is my password generator and it generates 8 characters and shuffles them. But i need to make it dynamic length. How would i go about doing that. So the output would be different length between 8 ...
2
votes
4answers
3k views

Creating symbolic link recursively

I essentially want to run this command... ln -s /opt/gitlab/embedded/service/gitlab-shell/hooks/ /var/opt/gitlab/git-data/repositories/web/*/hooks This would create a symbolic link in all folders ...
2
votes
3answers
1k views

How to nest quotes in bash commands

I want to test the result of this command: dmesg | grep "Firmware patch 1563" Therefore, I try to write something like this: if [ "`dmesg | grep "Firmware patch 1563`" == "" ] But it doesn't ...
2
votes
1answer
134 views

Replace pattern in file with pattern in second file

I want to replace part of a file's data, with data from another file. Suppose file1 has data as is written below and file2 has some data I want to store and replace file1 data from file2 from ...
4
votes
2answers
199 views

Where do bash completion functions come from?

I have a Raspberry Pi running Raspbian (Debian Wheezy). I entered set in a terminal and was surprised by the long list. This seems to be almost entirely git functions — ~3700 lines of them. ...
1
vote
1answer
271 views

Custom tab-completion in bash's `read`

Is there a way to "import" a list of words into bash's read builtin to have custom tab-completion? I've been writing a wrapper script for suckless' minimalist irc client "ii", and I don't have a way ...
0
votes
2answers
433 views

Get the file list in an HTML directory listing

I can get all files on the bash patches site by downloading them in a sequence: SEQ=$(seq -f "%03g" 1 30) for i in $SEQ; do wget http://ftp.gnu.org/gnu/bash/bash-4.3-patches/bash43-$i; done But ...
4
votes
3answers
4k views

How to escape single quotes correctly creating an alias [duplicate]

I've been given this one-liner to know how much memory my processes consume. $ ps -u $USER -o pid,rss,command | \ awk '{print $0}{sum+=$2} END {print "Total", sum/1024, "MB"}' Now I'd like to ...
2
votes
1answer
454 views

How to remove file log with file name

Assume, I have log files with this name format. NameLog.log.2014-09-27 NameLog.log.2014-09-28 NameLog.log.2014-09-29 NameLog.log.2014-09-30 NameLog.log.2014-10-01 NameLog.log.2014-10-02 ...
37
votes
3answers
7k views

What are the shell's control and redirection operators?

I often see tutorials online that connect various commands with different symbols. For example: command1 | command2 command1 & command2 command1 || command2 command1 && command2 ...
3
votes
2answers
269 views

How do I echo a lot of content in a bash script?

I would like to do echo "[this thing]" This thing is \documentclass{article} \usepackage{rotating} \usepackage{pdfpages} \usepackage{verbatim} \usepackage{amsmath, amsfonts, amssymb, textcomp, ...
5
votes
2answers
956 views

sed + how to delete the second character “.” from the line

how to delete the second character "." from the line what I have is this ( but its remove the first "." from output uname -r | sed s'/\./ /' 2 6.18-164.2.1.el5PAE while I need the following ...
1
vote
1answer
133 views

cd to a child directory of a symlink fails

To build a kernel module, you have to do make -C where -C is cd functionality. As my make failed a lot of times, I found this: [root@ror6ax2 modules]# ls -l /lib/modules/`uname -r` | grep build ...
0
votes
1answer
128 views

rpm + where RPM installed the files/scripts PATH

I installed the following RPM file rpm -Uvh --repackage /var/tmp/bash-3.2-33.el5_11.4.i386.rpm warning: /var/tmp/bash-3.2-33.el5_11.4.i386.rpm: Header V3 DSA signature: NOKEY, key ID 37017186 ...
0
votes
4answers
86 views

Bash multiple rename in one line: is possible?

Is possible to rename and substitute on fly with bash? for example i have VTS_01_1.VOB VTS_01_2.VOB VTS_01_3.VOB I want to rename for use in mencoder with movie_1.avi movie_2.avi,etc.. I ...
2
votes
2answers
61 views

Is there an improved version of “pick” that will work with filenames with spaces?

Is there a version of the pick script that will work properly with spaces in the filenames? This is a tricky question—pick is trivial to enhance to work with spaces in filenames, but the output ...
1
vote
1answer
2k views

Trying to multiply a float in bash not working [duplicate]

I have this script that is to rescale images to a percentage value #!/bin/bash percent=$1 echo $percent for img in `find *.png`; do echo Processing file $img width=$( mdls $img | grep ...
1
vote
1answer
98 views

Ran php file contents in bash, could some commands be executed?

I accidently pasted this in bash as super user on production server. Now I'm eating nails. I looked through each line and most of them produce syntax error. But is there something evil that could ...
1
vote
4answers
931 views

How to run a script in multiple instances ? ( Ubuntu server )

How can I run a script in multiple instances in Ubuntu server? For example, I have a long running script named scanner.sh placed in /usr/bin/, which I wish to run the script in 10 parallel ...
1
vote
2answers
922 views

A tiny and simple script fail and this is the output “No such file or directory”

The script is: #!/bin/bash IFS=" " command="ls /tmp" for file in `$command`; do echo $file done And the output is: $ ./test.sh ./test.sh: line 17: ls /tmp: No such file or directory
2
votes
3answers
1k views

Redirect stderr to a file, but create only if any stderr happened? [duplicate]

I'm running a command like: parallel --spreadstdin --line-buffered 'some_command 2> `mktemp --tmpdir /tmp/stderr`' | do_something The trick is that parallel creates a lot of processes and they ...
24
votes
3answers
3k views

How can I see the exact command line being executed inside some bash instance?

I have a long running bash instance (inside a screen session) that is executing a complex set of commands inside a loop (with each loop doing pipes, redirects, etc). The long command line was ...
19
votes
5answers
2k views

Why do I sometimes get repeatedly prompted with “>” in the terminal?

Alright, when I run certain commands the wrong way, (misspelled, etc.) The terminal outputs this: > instead of computername:workingfolder username$, and when I type enter it goes like this: > ...
4
votes
2answers
92 views

Long start time of MC due to bash function

I have next bash function to ensure new-lines after commands: user at terra in ~ $ echo "m" m user at terra in ~ $ echo -n "m" m↵ And the function itself in a .bashrc: function prompt_command { ...
1
vote
2answers
177 views

ffmpeg script - slicing a video into multiple slices

I am currently using ffmpeg to slice video files. I automated the process through a script called ffmpeg_split.sh. To view the script click here. When I run the script I have an error when trying to ...
-2
votes
1answer
222 views

How to use `cal` to run scripts? [closed]

I wrote a script and need to make it run with the cal command. How do I do this? This is my .bashrc: PATH=/usr/local/bin:/usr/bin:/bin:/usr/bin/X11:/lib/ast/bin:/home/$USER/bin:.
1
vote
2answers
1k views

how to shuffle characters of strings in bash?

i have this script where it generates random password but it needs to be shuffled. I couldnt find a way to do it. Please Help me. num=("0" "1" "2" "3" "4" "5" "7" "8" "9") special=("@" "#" "$" "%" ...
40
votes
3answers
2k views

How do I open an incognito bash session?

Is it possible to open an incognito session in bash? For example, when we need to enter passwords in commands and don't want bash to add them to history.
3
votes
3answers
1k views

Where are zsh and mksh incompatible with bash?

To what extent can other POSIX-compatible shells function as reasonable replacements for bash? They don't need to be true "drop-in" replacements, but close enough to work with most scripts and support ...
7
votes
2answers
518 views

What is the reliable way of getting each user's .ssh directory from bash?

I can parse the /etc/passwd with augtool: myuser=bob usershome=`augtool -L -A --transform "Passwd incl /etc/passwd" print "/files/etc/passwd/$myuser/home" | sed -En 's/\/.* = (.*)/\1/p'` ...but it ...
2
votes
3answers
5k views

Call sed to replace a string stored in a bash variable

I want to expand a variable in bash with sed or awk. This variable is an array. For example, the script must delete strings contained in array. I tried ARRAY1=( string1 string2 string3 ) sed -i ...
2
votes
0answers
178 views

How do I recursively apply default ACLs of a directory to its descendants?

If I have a directory with default ACL entries assigned to it, but some or all of its descendant files and sub-directories have access or default ACLs that do not agree with those defaults, how do I ...
2
votes
1answer
1k views

Updating bash against shellshock on Linux Mint 16

Apparently the LM package manager person is on holiday, so even an up-to-date Mint 16 box is vulnerable to the original Shellshock CVE. How do you update such a system meanwhile?
1
vote
3answers
1k views

auto creation of bash profiles?

Following the instructions at this nice walkthrough here. I have successfully configured my CentOS 6.5 Server to authenticate with my domain. Additionally, it only allows domain users of the group ...
1
vote
1answer
4k views

Which Debian patches fixes shellshock lcamtuf CVE-2014-6277 and CVE-2014-6278? [closed]

Note that this question is definitely not a duplicate of: When was the shellshock (CVE-2014-6271/7169) bug introduced, and what is the patch that fully fixes it? According to: ...
7
votes
1answer
579 views

history - List only successfully run commands

I'm wondering if there's a way to use the history command but only list commands that were run successfully. Likewise, would there be a way to list ones that produced errors? I know each command has ...
4
votes
2answers
196 views

When is 'if' not necessary?

In some scripts, I've seen if conditional statements written as: if [ some_conditional_statement ]; then # do stuff fi or [ some_conditional_statement ] && #do stuff Is the second ...
2
votes
1answer
451 views

bash_logout only run command on last logout

This command is in my .bash_logout script to delete a temporary directory when I logout after running some processing: /bin/rm -rf /tmp/tmpdir/ However, I usually have more than one connection to a ...
0
votes
2answers
97 views

Different results invoking bash diretly or via soft link

On my Red Hat Linux system /bin/sh is a link to bash $ ls -l /bin/sh lrwxrwxrwx 1 root root 4 Sep 27 13:17 /bin/sh -> bash Running this contrived test program directly gives me the expected ...
0
votes
3answers
163 views

Extracting index.php?dir=foo/bar/&file=bar2.jpg to foo/bar/bar2.jpg

I have a lot of files with names like: index.php?dir=IOP%2FFOO%2FBAR%2F&file=ScanImage001.jpg After replacing index.php? with nothing %2F with '/', dir= with noting and file= with nothing: ...
4
votes
1answer
3k views

How to use defined function with xargs

This is my code #!/bin/bash showword() { echo $1 } echo This is a sample message | xargs -d' ' -t -n1 -P2 showword So I have a function showword which echoes whatever string you pass as a ...
2
votes
0answers
33 views

git report moved lines

I want to track the number of additions and deletions that exclude moved lines. So if a commit has 10 additions, 5 deletions, and 3 moved lines, then I have 7 additions, 2 deletions excluding moved ...
5
votes
3answers
1k views

source my ~/.bash_aliases from a script not in ~/

I want to update my aliases from a script. I have some new aliases in ~/updateFiles/newAliases: alias ga='git add -A' I also have this update script ~/updateFiles/updater: #!/bin/bash cp ...
3
votes
3answers
2k views

How to copy, execute and retrieve data from a remote computer?

I am trying to run some calculations on a remote computer. Basically I want to copy some files to the computer, load a software, execute the calculation, then retrieve the data back. I have created a ...
19
votes
2answers
2k views

Are the terminal color escape sequences defined anywhere for bash?

I've used every so often colors in Bash scripting (mostly on CentOS), but to make their usage more convinient I end up redefining variables to color values: local GRAY="\[\033[1;30m\]" local ...
7
votes
1answer
8k views

Finding largest file recursively

I am trying to find the largest file in a directory recursively. If there is a subdirectory inside of that directory the function needs to go inside that directory and check to see if the largest file ...
4
votes
1answer
165 views

can we use something better than more for tab completion?

more is not as convenient as less. Is it possible to use something better than more for tab completion, when ls and then tab? Thanks.
4
votes
3answers
3k views

Why when I ssh into one server it shows bash and the other have my username?

So at work I have two web servers that I am able to ssh into. Both are RHEL 6.5 When I log into one, it shows this: [username@ldvweb01 /]$ When I log into the other one it shows: -bash-4.1$ ...