Bash is a free shell for Unix-like operating systems from the GNU Project.

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2k views

How can I extract only some specific folders from a tar.gz archive?

Let's say I have the archive website.tar.gz, inside is the following folder structure : home -mike -www -coolwebsite file1 file2 file3 etc. When I ...
3
votes
1answer
137 views

Attach command to execute when long-running thread returns

Let's say I've just started a command that will take a long time to execute, like hg clone the entire Pypy development set. Halfway through, I decide I'd like to run another process, like hg up, once ...
3
votes
1answer
825 views

How to write a script to sudo the last command [duplicate]

Usually, for some commands such as apt-get install xxx, I forget to add sudo first, then I need to retype it. What I want is in such cases, I just type a simple command, for example resudo. It will ...
3
votes
1answer
311 views

Force a bash script to run to completion where some items may stick

I've a Uni assignment I'm building that I need to run multiple times with multiple different parameters to check run times. At the moment I've a simple bash script that looks a little like the below - ...
3
votes
1answer
626 views

Can I make ssh-agent wait until I use ssh to prompt for a password?

I have ssh-agent set up to automatically start and prompt when I open a terminal window, as is explained here. It gets somewhat annoying though since many times when I open a shell I don't plan on ...
3
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4answers
321 views

Change directory upwards to specified goal

I'm often deep inside a directory tree, moving upwards and downwards to perform various tasks. Is there anything more efficient than going 'cd ../../../..'? I was thinking something along the lines ...
2
votes
2answers
140 views

What does “<>” exactly mean in “echo <> temp.txt”?

Non existing file $ ls file_not_exists.txt ls: cannot access file_not_exists.txt: No such file or directory $ echo <> file_not_exists.txt $ ls file_not_exists.txt file_not_exists.txt $ cat ...
2
votes
1answer
151 views

What this command :(){ :|: & };: does? [duplicate]

What does this shell command do in Linux :(){ :|: & };: How can it be used in Denial of Service attacks?
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votes
2answers
158 views

Unable to get profile variable using ssh

Unable to retrieve the profile variable using ssh. server2 ==> user apptst ==> bash profile has $APPHOME variable. Was trying to retrieve the value from server1 using ssh but failed. Used options ...
2
votes
2answers
2k views

Find difference with mtime - and +

Can someone explain the difference with mtime - and + switch as both are not bringing back the results I need. I'm looking to delete all files older then 5 days find /mnt/sdb1/tmp/ -type f -mtime +5 ...
2
votes
3answers
1k views

Running rdesktop through a SSH tunnel in one command

I am running ssh server -L 3392:192.168.1.138:3389 in one terminal window, then running rdesktop 127.0.0.1:3392 in another to connect to a Windows machine through an SSH tunnel. How can I merge this ...
2
votes
1answer
7k views

Howto switch / chage user id witin a bash script to execute commands in the same script?

Is there a way to switch user identity within a script (executed as root as part of an installation process) to execute some commands without calling an external script, then return to root to run ...
2
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2answers
559 views

Disable Bash's programmable autocompletion (based on command)

Bash in my Fedora 16 seems to autocomplete arguments based on the command itself. So if I for example type cd Tab … it will only show directories. There are however far too many commands where ...
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4answers
647 views

Background job in bash is shutting down when the firing window is closed: how to avoid this?

You can go quickly to the question starting reading from 'Having said that' The following are details on my specific needs I'm on lubuntu oneiric and trying to create a desktop launcher to start / ...
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5answers
4k views

Move all files in sub-directories to current directory?

I've got files in a bunch of subdirectories, and I'd like to flatten them out and move them all to the current directory. I found this question, but adapting the answer to: mv * . didn't work. I ...
2
votes
1answer
513 views

How can I remap Ctrl+C to send an interrupt signal with another key?

I've got a process in bash that I can call to stop using Ctrl+C. As far as I can see, this equals to sending an exit(1) signal. I would like to loop through these processes for a list of different ...
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votes
2answers
1k views

curl not uploading file to ftp

I am using curl to upload a file to ftp server. The same script is working on another system, but on this one after connecting to ftp it is not doing anything and connection times out. The detailed ...
2
votes
2answers
847 views

Remove bash startup behaviour (mac user)

When I start the terminal (which uses bash) a echoed message appears several times right before the message "You have mail." and it is added by someone that has used my computer. It also happens when ...
1
vote
1answer
155 views

Tmux causeing issues with Bash up-arrow

When using tmux, I have issues of ghost characters when using the Up and Down arrow keys in Bash. If I press UpArrow a few times and then press DownArrow a few times, then the first few characters of ...
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vote
2answers
3k views

Spaces in Linux environmental variables?

Given directory: /media/foo/can haz/bar, I have tried editing bash.rc with: export Foo=/media/foo/can haz/bar export Foo=/media/foo/can\ haz/bar export Foo='/media/foo/can haz/bar' export ...
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vote
1answer
1k views

Pass arguments to osascript via shell function in OS X Mountain Lion

The answer in How to open a new Firefox window with URL argument is broken in Mac OSX Mountain Lion (10.8.2). I can't comment on that answer or question, so I had to create a new question. It fails ...
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2answers
2k views

Diff and ignore lines missing in one file

I want to diff two files and ignore lines that are present in one file but missing in the other. For example File1: foo bar baz bat File2: foo ball bat I'm currently running the following diff ...
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4answers
2k views

less emulate a TTY to preserve piped color output

When you pipe something through less, the program usually discards color codes because it's not outputting to a TTY. So you have to add --color=always to the options for it to work. ls -l ...
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0answers
67 views

select files from a set [closed]

I need the Bash code for select file in a set of files. I use something like this find . -type f -name \*.txt to locate the set of files I want to work with. After that I would want select only the ...
1
vote
1answer
12k views

-bash: ls: command not found at Terminal on Mac OS X

I need to start using GIT for my projects from now on and I need to use some UNIX commands. but no matter what I do, I always receive "command not found" error. I installed MacPorts, but still cant ...
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2answers
106 views

sum numbers in different lines in shell

i have 8000 lines similar to this <Flow flowId="1" timeFirstTxPacket="+0.0ns" timeFirstRxPacket="+924100.0ns" timeLastTxPacket="+199984927558.0ns" timeLastRxPacket="+199675473275.0ns" ...
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2answers
631 views

How to organize files in accordingly named directories from command line under Linux

I have a directory filled with various files, differently named (i.e. not named with a specific pattern) and with different extensions, and I want to put each file in a newly created subdirectory ...
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3answers
615 views

How do I remotely execute scripts on multiple servers, mix output

Hi I'm looking for a piece of software or some sort of technique that would enable me to do following in one terminal window: Take as input a list of ssh-enabled machines with login, password and ...
0
votes
1answer
86 views

alias: extract options from command

Apologies for the bad title. I couldn't come up with a better one. I want to alias a command to another command, and extract options from the text of the command itself. I realize this is unclear, ...
0
votes
1answer
3k views

Sending commands to an existing screen session?

I have a Java app running in a screen session (A game server), and I'd like to be able to write a script to send commands to it periodically (with cron probably), but I'm not sure how to send commands ...
0
votes
1answer
156 views

Pause all but x CPU-intensive tasks

I've got about 50 folders of data to process, and I've got a ruby script that processes a folder's files (which folder it processes is based on a .yml configuration file). And a computer with four ...
13
votes
4answers
8k views

Ubuntu grep, find etc: “Permission denied” and “No such file or directory” output

When I grep or find something I always get annoyed by the "Permission denied" and "No such file or directory" notice, smth like that: johndoe@johndoe-desktop:/$ grep -rnP 'YII_CORE_PATH' ./ | grep -v ...
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4answers
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Understanding pipe in bash

I dont quite understand how pipes work in bash. I know that it takes an output from one command as the input in another command. What an output is i can get because it's what the command prints out ...
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votes
5answers
6k views

What does the linux pipe symbol “|” do? [duplicate]

Here is a command that sorts files in a folder in reverse order ls | sort -r What does the | symbol in that command do? What I'm really looking for here is high level (easy to understand) ...
8
votes
5answers
2k views

delete or rename a file with \r as the file name

I have a pesky little file whose name appears to be single character, and that character is a \r How can I delete this? This is what I get with ls -bl: -rw-rwxr--+ 1 root ...
8
votes
2answers
935 views

Making bash TAB completion more like cmd.exe [duplicate]

I wondered if theres a way to do rotational style completion in bash similar to the behavoir on cmd.exe, I've found it speeds me up in regard to entering commands
8
votes
3answers
5k views

Spawn New Cygwin Window from Within Cygwin

I can't figure out how to launch a new Cygwin session from within Cygwin, similar to launching a new terminal from within bash with: gnome-terminal It's probably easy but I am missing something. ...
7
votes
3answers
1k views

futurama bash scheme

Is there a color scheme for the BASH shell that matches the blackboard colors on futurama? (If it matters, I'm on OSX.)
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votes
2answers
202 views

Differences in bash scripts between $@ and $*

Which are the differences between $@ and $* ? For example I see no differences here: #! /bin/bash echo with star: $* echo with at sign: $@
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votes
7answers
7k views

Linux: rename file but keep extension?

In Windows/DOS, I can say rename myfile.* yourfile.* to change the name but keep the extension. How is that accomplished on Linux? The man page only suggests how to change the extension, but that's ...
5
votes
3answers
300 views

How to remove a file with name starting with “-r” using cli [duplicate]

I have been creating odd-named files every once in a while, e.g. $ls -rthl $-rw-r--r-- 1 shamil hep 290 Aug 13 11:58 -rf And interestingly it is impossible to remove this file with rm -f -rf I ...
5
votes
3answers
5k views

BASH - merge directories when using mv

I just started using BASH, so I can move all contents of a directory to another. But the issue is, I was expecting it to merge the directories. I am using cron job to run this script. #!/bin/bash ...
5
votes
3answers
419 views

How do I detect when I a terminal gets focus in Linux?

I want to be able to time how long I spend in front of a terminal. I'm thinking the best way will be to have some sort of timer that starts and stops when the terminal gains/loses focus. And it will ...
5
votes
2answers
2k views

Exclude folder using 'Find' command

Guys, I'm using the find command on a Mac to search for a folder called 'test1'. Now 'test1' folder could be present in the '.Trash' folder also. How do I exclude the '.Trash' folder from getting ...
5
votes
2answers
454 views

on quit, 'less' does NOT clear its contents when run in a 'screen' session [duplicate]

Possible Duplicate: Using screen, commands like less and man don't clear the screen afterwards When I quit 'less' in a normal bash, it clears the previous contents displayed by 'less' ...
5
votes
2answers
1k views

Change directory cd to another terminal's cwd

I would like to create a command like cd - (lets call it cdp) that will change directories to the last changed-to directory from another terminal window similar to the option to open a new terminal in ...
4
votes
3answers
2k views

Sublime Text Editor command not found

I have installed Sublime on my Mac Lion Laptop, and followed the guide here http://www.sublimetext.com/docs/2/osx_command_line.html but as always it did not work. I dont have a ~/bin directory on my ...
4
votes
3answers
814 views

How do I edit previous lines in a multiple line command in Bash?

When entering a command which spans multiple lines in Bash, how do I edit previous lines? I'm a Linux Mint (Lisa) user using GNOME Terminal. For example, let's say I type: $ echo "foo bar > baz ...
4
votes
4answers
6k views

Setting ID3 title tag to be equal to MP3 file name

Has anyone got a bash script that will go through a media library and set the id3 title tag of each MP3 file to be equal to the file's name? I'm open to other automated methods too. It can be a GUI ...
4
votes
1answer
640 views

How to make bash alias invocation conditional on PWD?

I currently have this alias: alias cmakerel='cmake -DCMAKE_BUILD_TYPE=Release -Wno-dev ../../ && make -j4' Essentially, it will call cmake to do an out-of-source build from PWD. It works ...