The shell is unix's command-line interface. You can type commands in a shell interactively, or write scripts to automate tasks. Use this tag for questions applying to /bin/sh and most compatible shells (ash, bash, ksh, zsh, …).

learn more… | top users | synonyms (1)

3
votes
1answer
4k views

Determine current shell name [duplicate]

Possible Duplicate: How to test what shell I am using in a terminal? How do I determine the current shell path or shell name? I only really need to distinguish sh and bash, however a ...
5
votes
1answer
187 views

find usage - command line vs script

I am seeing different results from the find command between being run manually on the command line vs run in a script. If I run the following on the command line: find . -name '*.txt' ! -name ...
19
votes
8answers
4k views

What is the utility of the : command in shell scripting, given that it explicitly does nothing?

In the answer to this question about comments in shell scripting, it is indicated that the : is a null command that explicitly does nothing (but is not to be used for comments). What would be the ...
3
votes
2answers
557 views

issues with GNU tail -f and combination of commands

$ tail -f /logs/filename.log | awk '!(/list)' I am able to run this command in GNU Linux flavour But when I written in a script it is not working. test.ksh: variable="/logs/filename.log | awk ...
8
votes
4answers
5k views

Recursively rename subdirectories that match a regex

I have a media server with a folder called Series. (/media/Expansion2/Series/) In it, I have (surprise!) TV series. These are just the show names, e.g., /media/Expansion2/Series/The Big Bang Theory/ ...
145
votes
5answers
325k views

How do I grep for multiple patterns?

I want to find all lines in several files that match one of two patterns. I tried to find the patterns I'm looking for by typing grep (foo|bar) *.txt but the shell interprets the | as a pipe and ...
3
votes
4answers
4k views

Renaming files works, but soft links point to the old names. How can I fix that?

For example, I'm renaming many files inside a tree like this: [bash]$ for file in `find . -name "*gsf*"`; do `mv $file ${file/gsf/msf}`; done That renames all the instances of "gsf" in file names ...
1
vote
3answers
4k views

Using awk to process ls output with spaces in filenames/paths

All, I have a script in which I use find command to filter out all png files in a given folder and list them along with their size. I want the output in the following format: someFile.png => 1.2K ...
9
votes
4answers
36k views

Change font in echo command

Is it possible to change the font attributes of the output of echo in either zsh or bash? What I would like is something akin to: echo -n "This is the font: normal " echo -n $font=italic "italic," ...
51
votes
5answers
2k views

cd by just typing the directory's name?

I either had this somewhere 20 years ago or I dreamed about it. Basically: If if type blobblob I get blobblob: command not found Fair enough. I would like it so that when my shell gets those ...
1
vote
1answer
196 views

Load command parameters from upper level file

I've come across an interesting problem that I have not yet been able to solve satisfyingly. Consider a note taking command that takes two arguments: note $project $note That simply files the ...
1
vote
1answer
2k views

Running shell commands in .sh file results to error

I have two following linux shell commands: echo 'CPU type and model' cat /proc/cpuinfo | head -5 | tail -1 When i run these commands directly in Terminal, i get this result truly: CPU type and ...
70
votes
4answers
21k views

What is the difference between “&&” and “;” when chaining commands

What is the difference between the following methods of chaining commands? cmd1; cmd2 cmd1 && cmd2
25
votes
3answers
2k views

Which are the standard commands available in every Linux based distribution?

I would like to know which are the standard commands available in every Linux system. For example if you get a debian/ubuntu/redhat/suse/arch/slackware etc, you will always find there commands like: ...
2
votes
1answer
295 views

Delete repeated words between brackets inline

Our input looks something like 2012-04-17 [GBPGBP] 2012-04-13 [GBP GBP] 2012-04-13 [GBP] 2012-04-11 [GBPGBP] 2012-04-11 [GBP GBP] 2012-04-10 [GBPGBP] 2012-04-06 [GBP GBP GBP] 2012-04-17 ...
7
votes
3answers
2k views

Change the color of the file name text

I am writing scripts to initialize and configure a large system with many components. Each component has its own log file. I would like to change the color of the component file name to red whenever ...
1
vote
2answers
869 views

Is there any simple way to change one line in a lot of files?

I'm trying to use PHP CodeSniffer, and here's the result: ----------------------------------------------------------------- A TOTAL OF 3008 ERROR(S) AND 380 WARNING(S) WERE FOUND IN 46 FILE(S) ...
2
votes
2answers
1k views

log remote X session from ssh (PuTTY)

I've googled alot about this and can't find a way to do this (or if it's even possible) I want to log a user on a remote machine in his X session (Gnome) from a ssh in a windows machine with PuTTY. ...
2
votes
1answer
2k views

Where does plink (from Putty package) search for remote commands?

I need to use plink (or something similar if you have something on mind) to get the output from Debian remote machine onto my Windows box. This works e.g. in this case : plink 192.168.1.5 "ls" > ...
9
votes
3answers
3k views

Substituting strings in a very large file

I have a very long series of urls with no separating character, in the same format as below: http://example.comhttp://example.nethttp://example.orghttp://etc... I want each URL to be on a new line. ...
2
votes
4answers
2k views

Change password in headless mode

I am building a script to fully automate a VPS setup, and I need to change the root password. I would like to avoid typing it as the script is running through SSH. Is there a way to redirect an ...
5
votes
1answer
2k views

How to create a confirmation question in Linux?

I have a certain command (git push server-name) that has major consequences. How to require confirmation for this command only? It should ignore white space. The confirmation could be Enter 'yes i am ...
11
votes
4answers
9k views

symbolic link to a directory and relative path

I've created symlink with absolute path to the directory (Blink) and have for example following tree: $ ls -l /tmp/A total 0 lrwxrwxrwx 1 root root 6 Apr 3 12:27 Blink -> /tmp/B -rw-r--r-- 1 root ...
4
votes
2answers
2k views

Can I read and write to the same file in Linux without overwriting it? [duplicate]

Possible Duplicate: How can I make iconv replace the input file with the converted output? I frequently connect to amazon ec2 using their public DNS names ...
4
votes
3answers
1k views

How to skip file in sed if it contains regex?

I currently use the following simplified command to remove trailing whitespace and add a newline at end of file where needed: find . -type f -exec sed -i -e 's/[ \t]\+\(\r\?\)$/\1/;$a\' {} \+ As ...
2
votes
3answers
919 views

loop to paste specific files in different directories

I some directories that contain a similarly named file eg (*Sample_name*.base.coverage.txt). And I would like to paste all of the *base.coverage.txt files together. I have something written, but its ...
6
votes
1answer
256 views

How to run programs with arguments like 'arg=val' (e.g. dd) in rc shell (Linux version ported from Plan9 OS)?

I'm trying to use rc shell (Linux port from Plan9 OS) and get 'syntax error' messages when using programs with arguments like arg=val. ; dd if=/dev/zero of=/dev/null syntax error ; ls --color=auto ...
4
votes
3answers
901 views

Why read works if stdin is redirected to fd4?

What does the following script mean? exec 4<&0 0</etc/XX/cfg read line1 exec 0<&4 It redirects fd0 to fd4, and "/etc/XX/cfg" to fd0. So why does read still work, shouldn't that ...
2
votes
1answer
10k views

How can I delete a hidden folder?

I want to delete many configuration folder in my home user folder but I can't figure out how to delete them. How can I delete a hidden folder?
4
votes
2answers
999 views

Zsh — more intelligent autocorrection

Is it possible to make Zsh stop trying to correct arguments that are not meant to be files with files from the current directory without turning off correction completely or limiting it to setopt ...
0
votes
1answer
218 views

How to use a password as an external variable in shell?

I have this MySQL backup script that I use to back up MySQL databases. Very useful, and it runs on fixed intervals using a cron. However, I need somehow provide this script with the MySQL password. ...
1
vote
2answers
810 views

How does this shell command work?

The following command puts the content of the local id_rsa.pub into the authorized_keys file on the host. But I don't quite understand how cat and | works together to achieve this goal, can someone ...
5
votes
3answers
4k views

Remove many many many files from a folder

I have a folder with 137795 files in it. I need to delete all of them. When I run rm * I get -bash: /bin/rm: Argument list too long. How do I get past this error?
0
votes
1answer
2k views

How to pkill from a script?

How can I write a script that basically just runs pkill -HUP inetd? I want to restart inetd via a script so I can schedule it to run at a particular time. I tried to write it myself, but I'm getting a ...
1
vote
0answers
618 views

Manually setting environment variables for Metasploit

How do I set manually environment variables for Metasploit, when I execute db_driver I get this message: [*] No Active Driver [*] Available: [*] DB Support: Enable the postgresql driver ...
1
vote
1answer
825 views

What is the difference between $var and “$var”? [duplicate]

Possible Duplicate: $VAR vs ${VAR} and to quote or not to quote I assigned a variable var a value as follows: pradeep@pradeep-laptop:~$ var="Pradeep > is > a good > boy" ...
19
votes
4answers
9k views

Four tasks in parallel… how do I do that?

I have a bunch of PNG images on a directory. I have an application called pngout that I run to compress these images. This application is called by a script I did. The problem is that this script does ...
15
votes
1answer
12k views

ls taking long time in small directory

Running Ubuntu, I open a terminal and do sudo bash cd / ls | head -n 1000 And predictably about 20 directories are returned. However, if I do an ls, and don't pipe it into anything, the ls just ...
4
votes
1answer
5k views

Run xterm with login shell or not?

Per default xterm starts an interactive shell. But you can also configure it to start an interactive login-shell. That means that with starting an xterm you get the same kind of shell like logging in ...
40
votes
1answer
69k views

How do you extract a single folder from a large tar.gz archive?

I am using this command on a 5GB archive tar -zxvf archive.tar.gz /folder/in/archive is this the correct way to do this? It seems to be taking forever with no command line output...
4
votes
2answers
327 views

Why 2 linux machine behave differently with command of the same syntax?

I am using 2 machine , which is both Red Hat Enterprise Linux AS release 3 (Taroon Update 2) ( I check it in /etc/*-release ). I checked they are using the same default shell by ps -p $$, which is ...
8
votes
2answers
933 views

How do I add network or user source connection data to history entries?

I would like to modify the history settings for all users on the systems that I manage. I would like it to contain the information from the connecting terminal like from who sysadmin:/ # who sysadmin ...
3
votes
1answer
246 views

How can I pipe a path to pushd?

This seems like it should be easy enough to do, but I'm clearly not understanding something fundamental about piping output back and forth. I'm trying to do something like this: bundle show ...
4
votes
2answers
897 views

List of script( location)s that get run automatically, and when?

Does anybody know (of a resource listing) what scripts are run automatically, and when, from the moment I startup the computer until it's shutdown again. I know several places where I can add scripts ...
3
votes
0answers
401 views

How are you organizing your $HOME? [closed]

I've always wanted to know more about how people (power users and lambda users) were organizing there $HOME. The trend is currently is using xdg-users-dirs which define a set of most used folders like ...
0
votes
2answers
7k views

Trying to set JAVA_HOME in ~/.bashrc

I have added this line at the end of ~/.bashrc export JAVA_HOME=/usr/java/jdk1.5.0_07/bin/java But when I execute echo $JAVA_HOME, I don't get anything as output, I expected ...
2
votes
0answers
114 views

How does << work and what is it called? [duplicate]

Possible Duplicate: Correct textual name for << I am learning about Go and saw this usage I've never seen before (from http://golang.org/doc/install.html): $ cat >hello.go ...
4
votes
4answers
746 views

Get input from editor (vim/nano/emacs/textmate?)

I was just curious if there's a way to get input not from StdIn but from $EDITOR - be it vim, nano, emacs or even a non-command-line-editor (MacVim/TextMate). What are the ...
11
votes
3answers
1k views

Escape sequences in output of script called from ncurses application

I'm currently running mcabber as my Jabber client (which uses ncurses) in a tmux session on my homeserver. Locally i run iTerm2 as a terminal emulator, which supports the triggering of growl ...
2
votes
2answers
799 views

Shell script output incorrectly splitting while being passed as an argument to script

Let's say I have the following two shell scripts: #!/bin/sh #This script is named: args.sh echo 1 "\"Two words\"" 3 , and: #!/bin/sh #This script is named: test.sh echo "Argument 1: "$1 echo ...