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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3
votes
2answers
176 views

bash equivalent of zsh's $@[2,$#]

(NB: the motivation for this question is only to improve my bash programming know-how.) I want to know the bash equivalent of zsh expressions such as $@[2,$#], which directly address a range of a ...
3
votes
4answers
2k views

Why is bash interpreting characters that I have character escaped? [duplicate]

Why is it that when I run curl against a REST API, the special characters (!) in my key are interpreted by the shell? curl https://foo.my.salesforce.com/services/data/v28.0/ -H "Authorization: ...
3
votes
1answer
3k views

viewing dll and exe file properties/attributes via the command line

I have a need to see some additional file properties for exe and dll files. If I open windows explorer and add the additional columns to my view, I can see things like Company, Copyright, Product ...
4
votes
2answers
181 views

What configuration can insert lines between commands?

I've noticed on some Linux servers, that bash has a very elegant feature that adds visual breaks. What program is it that appends the -------- <time> after each command?
3
votes
2answers
289 views

Preventing accidental directory deletion. Making an alias that contains options?

I use an alias to prevent me from accidentally deleting files, and I would like to do something similar for directories. For files, I have the following added to my .bashrc: alias rm="rm -i" I ...
14
votes
5answers
695 views

Use same arguments with different command [duplicate]

Here's something I find myself doing often: less super/long/file/name Followed by: vim super/long/file/name Is there an easy way to pass the args of the previous command over to the next? SO I'd ...
4
votes
1answer
264 views

Pipeline and redirection understanding

Please explain this script (from ABSG. Ch. 20): exec 3>&1 # Save current "value" of stdout. ls -l 2>&1 >&3 3>&- | grep bad 3>&- # ...
51
votes
5answers
23k views

What is the purpose of the hash command?

If you run hash it shows the path of all commands run since the hash was last reset (hash -r) [root@c04c ~]# hash hash: hash table empty [root@c04c ~]# whoami root [root@c04c ~]# hash hits ...
7
votes
4answers
3k views

Bash script to rename files from a text file source

I'm fairly new to bash; I can just about perform simple administrative tasks with simple commands 1 at a time. However, I've been tasked with renaming some files in a directory using a text file as ...
1
vote
1answer
105 views

Mass file+folder+directory move

So we have a bunch of src files that are old and out-dated and need to be moved to our new NAS storage. (I don't know why we are keeping them). Is it possible to copy all the files and folders with ...
1
vote
3answers
392 views

Taking Backup of files of particular limit in unix

Here is the scenario, I have 1000 files in a folder each ~3 MB. I want to zip all files into 50MB each zip and remove the original files. NOTE: 50MB may contain 20 files or 10 files but that zip ...
2
votes
2answers
5k views

Get list of all files by mask in terminal

I want to find all *.h,*.cpp files in folders with defined mask, like */trunk/src*. So, I can find separately *.h and *.cpp files: find . -path "*/trunk/src/*.h" find . -path "*/trunk/src/*.cpp" ...
0
votes
1answer
2k views

if condition, loop in grep [closed]

Could someone please provide help for me. I tried to start writing a shell script but am getting hung up with this issue. I need to grep commands "adb shell ps" and find in it 3 processes with names: ...
2
votes
0answers
5k views

ssh-agent not getting set up (SSH_AUTH_SOCK, SSH_AGENT_PID env vars not set)

I set up a new user account for a friend on Kubuntu 12.04. When he uses ssh he gets this error: Could not open a connection to your authentication agent We're running ssh in some bash scripts. ...
3
votes
1answer
470 views

Variable declaration in parallel sh -c …

I've been trying to process the output of find with parallel, which in turn invoked a shell (some textual substitutions were needed). I observed some strange behaviour, which I cannot really explain ...
1
vote
1answer
324 views

Launch 2 celery processes via cron

I'm trying to chain some commands to periodically check/launch two processes via cron (I'm on a shared host, can't change things around). After a lot of googling around, all the things I've done don't ...
4
votes
5answers
5k views

grep for multiple strings in files, and then list the files in the order of size

I am in a folder with lots of .txt file, I would like to find all the files which contain both stringA and stringB (not necessarily on the same line), then list these files in the order of the size ...
3
votes
2answers
103 views

How to switch to editing command in text editor [duplicate]

When typing a complicated command that started on the command line in Bash, how do I switch to editing it with ViM?
3
votes
2answers
798 views

Why can't pgrep find scripts started via env?

For example: $ cat foo.sh #!/usr/bin/env bash while true; do sleep 1 ; done $ ./foo.sh & $ pgrep foo.sh $ Contrast with: $ cat bar.sh #!/bin/bash while true; do sleep 1 ; done $ ./bar.sh & ...
1
vote
1answer
742 views

Non-ASCII characters handled incorrectly on command line

I have a problem with non-ASCII characters in the Terminal on Mac. If I write: echo ÆØÅ Then press Enter, Arrow Up, Arrow Left, so the cursor is between the Ø and the Å, then write X, then the Å is ...
1
vote
1answer
778 views

Cron automated bash script to run run 1 bash script then another, plus integrity check

So I have a custom in-house app developed by a 3rd party. When the app is running, I can verify it is running with the "screen -ls" command. As long as screens are running for rails and freeswitch ...
5
votes
2answers
838 views

Why do I need the double dash before argument passed to sh by xargs -I for it to work properly?

Sorry for the mouthful title. Here is the command in question find . -name "*.txt" | xargs -Ifile sh -c 'echo $(basename $1) ' -- file So without the double dash the file is not passed to sh and ...
3
votes
2answers
20k views

Checking and changing file permission with script

I'm new to bash and I can't get a script working. This is the code that I have: #!/bin/bash file=~/scripts/text.txt if [ -e $file ] then echo "The file exists" elif [ ! -e $file ] then echo "The ...
2
votes
2answers
20k views

How do I process ifconfig output to determine my link speed?

Here's script I wrote out of boredom, for download speed test: #!/bin/bash get_ispeed() { echo $(ifconfig eth0 | grep bytes | grep RX | cut -d ':' -f 2 | cut -d ' ' -f 1); } for((;;)); do ...
4
votes
2answers
72 views

Is it possible to notify/warn that current path isn't a valid symlink anymore?

Let's say we have ./a and ./b directories. Then we create a symlink using ln -s a x and entering it cd x The pwd would be x Then in another terminal we change the x so that it pointed to b. But the ...
1
vote
2answers
1k views

how to escape unusual/uniq characters from expect scripts?

in expect script I can set any command or character to run it on remote machine but the sad thing is that expect cant send the same character as they defined in the expect script for example I want ...
3
votes
2answers
191 views

How to make .bashrc call dependant on tmux program being installed?

I have a section in my .bashrc that fires up the tmux program (terminal multiplexor). However if the tmux program isn't installed (say I'm setting up a new computer) then having this in my .bashrc ...
2
votes
0answers
128 views

Linux child processes not being culled [closed]

This is causing significant problems for script portability between BSD and Linux. I am on a CentOS 6.4 where this happens. I have a nice compact test case: bash -c "inotifywait -mcr . | sed ...
11
votes
1answer
9k views

Piping search term (not filename) to grep

I want to pick out certain lines containing a given number from a file. The file I want to search is called os_clusters/piRNA_clusters.bed. awk '{if (a[$0]++ == 0) {split($0,b,"."); ...
7
votes
1answer
5k views

how to enable command history of shell

I am using ubuntu 13.04, in this the command history of the shell is getting erased on close. Can someone tell me how to prevent this from happening?
3
votes
1answer
209 views

Where is the bash feature to open a command in $EDITOR documented?

I have recently discovered that if we press Ctrl+X Ctrl+E, bash opens the current command in an editor (set in $VISUAL or $EDITOR) and executes it when the editor is closed. But it doesen't seem to be ...
2
votes
4answers
2k views

Bash source — select the right function when two sourced files have the same function name?

My bash script sources a script file (call it file2.sh) according to an argument. (It is either sourced or not.) The script file2.sh contains a function "foo" (call it a modified or improved version ...
34
votes
5answers
10k views

How can I `alias sudo !!`?

I'm trying to set an alias for sudo !! in Bash. I tried alias sbb='sudo !!', but it interprets that as a literal !! and prints sudo: !!: command not found If I use double quotes, it substitutes ...
-1
votes
2answers
104 views

What's wrong with this tar command? [closed]

find /informatica/dev/SrcFiles* -mtime +7 -and -size +1M -exec tar -rvf files.8.2.2013.tar {} \; This command is running/working correctly and I'm not sure whats wrong. I want to find the files that ...
2
votes
0answers
542 views

gnome-terminal cmd leaving processes open after closing parent window

The following simple command should demonstrate my issue: gnome-terminal --tab -t "Tab 1" -e "/bin/bash" --tab -t "Tab 2" -e "/bin/bash" This should open a new window with two tabs and an active ...
5
votes
3answers
484 views

Can you pipe to a .bash_profile function?

I received a great function for highlighting files in Apple's finder using the command-line. It's basically a wrapper for osascript. I got it from Mac OS X: How to change the color label of files ...
3
votes
1answer
436 views

How to create a file with the name specified in ASCII encoding?

I want to create a file that is called ascii 007, which is the bell symbol, which is not printable. I tried nano $'\007', but that just created a file called ?; cat ? print the test content, that I ...
0
votes
1answer
2k views

Changing title without changing prompt on Cygwin

I have the following shell script function from this site that allows me to change the title in both Putty and Cygwin. In Putty connected to a Linux host it changes the title and leaves the prompt as ...
1
vote
2answers
2k views

Removing specific files recursively using rm or something simple?

I have a root folder with a text file in it called pairs.txt. Within that root folder are other folders with text files called pairs.txt in them. Is there a simple way to remove them using rm? I ...
1
vote
2answers
155 views

find command help

I'm struggling using the find command that will allow me to find all files that were modified over 7 days ago and that are larger than 1 MB. Here's what I have - find /path/to/files* -mtime +7 | ...
10
votes
1answer
963 views

How many different ways can you create an “alias” in Bash?

I only know of two ways: alias foo=bar and function foo() { bar }. The reason I'm asking is that - all of a sudden in one of my bash sessions - I cannot run the ln command because bash is erroring ...
1
vote
2answers
1k views

While reading from a file, choose specific fields and compare them with another file in Unix bash?

I have a CSV file that contains the columns a,b,c,d and e and another file that contains column z. While reading line by line from the 1st file I want only fields c and d and at the same time I want ...
7
votes
2answers
1k views

In Bash scripting, what's the meaning of “ $! ”?

If I'm assigning a variable with temp=$! what would it be its value?
6
votes
4answers
1k views

Shell, Concatenating 2 strings to reference a 3rd variable

I am trying to do the following in my script: #/bin/bash -x var1=www var2=www2 var3=www3 var4=www4 for i in 1 2 3 4; do echo \$var$i done Obviously, this doesn't work as expected and results in ...
5
votes
2answers
36k views

bash setenv command is not found

every body I am new in centos server I am getting a error while using following command setenv CLASSPATH /path/mysql-connector-java-ver-bin.jar:$CLASSPATH error is bash setenv ...
2
votes
3answers
2k views

When I try to run a comment I get the error `The command could not be located because '/usr/bin' is not included in the PATH environment variable'

when I try to run in the terminal, I get the error The command could not be located because '/usr/bin' is not included in the PATH environment variable. e..g. jeper@jeper:~$ clear Command 'clear' is ...
4
votes
3answers
1k views

timeout without killing process in bash

I have a main script that I'm running, and from it I have a second "slow process" I want to kick off, and "do something" in the main script if it doesn't complete in the time limit -- depending on if ...
3
votes
1answer
100 views

m key not registering in Bourne-Again shell 3.2, OSX. Guesses?

Just lowercase m, and just when invoked interactively through /bin/sh. The keyboard works fine, and usually everything works fine. I almost never use /bin/sh, just /bin/bash, so it was somewhat ...
1
vote
4answers
83 views

Extract data from line and prepend to the line?

Ok, I have some data in the form: <a href="/praha/jaktovidi/_zprava/jak-to-vidi-rektor-richard-hindls-5-cervna--1220102"> <a ...
15
votes
1answer
25k views

delete files matching pattern

I need to recursively remove all files in all subdirs where the filename contains a number followed by an 'x' followed by a number, at least two times. Example: I'd want to remove these files: ...