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
vote
1answer
70 views

Cannot get 'match-hidden-files' to work

I have been trying to get 'match-hidden-files' to work on bash 4.3.11, but I can't. I wanted to make sure it's not something I'm doing wrong. $ grep match-hidden-files .inputrc set ...
0
votes
3answers
108 views

How do I search a file for a string then use it as a variable?

I have an XML file that looks like this: <id>456</id> <root> <value>1</value> <intNum>2</intNum> </root> <root> <eulav>1</eulav> ...
1
vote
3answers
442 views

WMCTRL not working after starting xfce4-terminal

If I type these two commands in a terminal: xfce4-terminal --hide-menubar --hide-borders --hide-toolbars --title=dt wmctrl -r dt -e 0,10,10,720,720 I get the desired result (position and resize of ...
3
votes
3answers
83 views

How can I base the file name off of an already existing variable?

I'm using this to delete lines that don't match a pattern: $ egrep "pattern1|pattern2|pattern3|pattern4|pattern5" But now I need to do it automatically, so I'm setting a variable like this: $ ...
2
votes
1answer
626 views

“Argument list too long” while executing cut and sed in a subshell to set a variable

I have written a bash script with has a python code embedded within it. What I did was read in the file and cut it with the below bash commands and then I exported it so that the python code could use ...
1
vote
2answers
972 views

bash if statement troubles [Error==Error]: not found [duplicate]

Everytime I run my script the following if statement gives me the error; script.sh: [Error==Error]: not found or script.sh: [Error==-2]: not found if ["$P1"=="$P2"];then echo $name ...
0
votes
2answers
563 views

Delete consecutive lines if patterns match in each line

Good day, I was wondering how to delete to consecutive lines when this pattern is found: /^pt [a-z]\npy [0-9][0-9][0-9][0-9]\n// Expected Input pt a py 01234 pt b cd abc py 5678 Expected Output ...
2
votes
1answer
178 views

Strange leading whitespace in OPTARG when using getopts

I spent quite a while researching the problem I encountered but none of the getopts tutorial say anything about the leading whitespace in OPTARG when using getopts. In bash(on Ubuntu and OSX), ...
0
votes
1answer
438 views

Launch BASH script by clicking icon and preserve terminal icon

My problem is pretty simple, but I must admit, I don't know any elegant solution. I have a problem, that I often accidentally click different icon that I wanted. It's really very unpleasant, so I've ...
0
votes
1answer
554 views

How to run commands on a variable containing a date?

I need to be able to take a date in the format of "MM/DD/YY" and change it back into the default date format (Fri Oct 31 17:23:07 CDT 2014). This is driving me crazy. The code below may look ...
3
votes
1answer
272 views

How to run a program that has its own command line within a shell script program

I need to write a shell script to automatically run a set of files through an existing program ~1000 times. The program I'm trying to run them through is accessed through command line as follows, then ...
1
vote
1answer
172 views

“Pipe” command to new bash shell?

I want to add my private key to the ssh-agent and I'm following these instructions. According to this the command ssh-agent bash spawns a ssh-agent bash and I can add my key afterwards using ...
5
votes
3answers
906 views

Hide ouput of bash while running automated script.

I have a couple of scripts in my bash file, that should do certain tasks, say like ... #!bin/bash yum -y update service restart nginx yum install atop cat /var/log/somelog.log > ...
1
vote
1answer
247 views

How to enter date as an option in a bash command? [duplicate]

I want to enter the current date (ideally in the form YYYY-MM-DD hh:mm) as an option in a bash script: I tried /usr/local/bin/growlnotify -t "PMK" -m date but then the variable -m inserts the ...
0
votes
1answer
317 views

Why isn't this `expr … | bc -l` command working?

I'm noticing an error: bash: syntax error near unexpected token `-105.5*7+50*3' When executing the below script/expression: expr (-105.5*7+50*3)/20 + (19^2)/7 | bc -l Is there any other way ...
4
votes
3answers
388 views

Arithmetic operations with expr and variables

Why won't this statement work? total=`expr $mPercent / 100 "*" .482 + $fPercent / 100 "*" .518` mPercent is a number as a result of an awk statement, as well as fPercent. I also get "expr: ...
1
vote
2answers
484 views

How does Bash pipe large amounts of data?

Let's say you want to cat the contents of a really big file, but want to view it a few bits at a time. Let's say one were to do the following: $ cat /dev/sda1 | less As a programmer of languages ...
1
vote
3answers
45 views

Command that passes its input through to output AND performs command?

I'm trying to use the quote program to make a little shell script that'll keep updating the stock prices every second. quote has to access the Internet and therefore has a small delay when it runs. I ...
0
votes
1answer
196 views

How can a script ask me questions?

I am using this script to analyse data: #!/bin/bash in=/autofs/cluster/transcend/mega/scripts/ insub=/autofs/cluster/transcend/mega/dtn/20141015/123 out=/autofs/cluster/transcend/mega/scripts/1256 ...
1
vote
3answers
500 views

Find and delete duplicate txt files

I have a folder with around 300 text files, is there any command that reads every every file indivdually and deletes the duplicate files? I mean the content and not the file names.
3
votes
5answers
955 views

List files with line count and date

I want to be able to list files showing the number of lines the each file has and the date. I can happily get the line count using wc -l *. Not a problem. I can get the date using ls -l. Is there a ...
3
votes
2answers
215 views

What can I do if bash stops echoing?

One of the applications I use at work sometimes screws with my bash and so I don't see my own input anymore. I.e. $ echo foo foo $ becomes $ foo $ I incorrectly tried to run stty -echo which ...
1
vote
1answer
154 views

Open a new bash with sudo powers without reentering the password [duplicate]

I find very useful to have more terminal tabs in different current working directories. But if I need sudo privileges I need to reenter the password for every shell. Is there not a way to extend the ...
2
votes
1answer
3k views

How to execute recurring Bash script at specific times?

How would I set a script to execute on every Tuesday and Thursday at 11:50am? I've been looking at the at command, but I can't conceive how to use it the way I need to from its man page.
2
votes
1answer
285 views

Simulate Initial Login of user without using sudo

I'm writing a script to interface 2 third-party programs. (Datadog and AWS) The data mining script uses sudo -u to run my script. The script that I need to retrieve data from will segfault if ...
2
votes
1answer
241 views

How do I choose a file names with consecutive numeric suffixes?

I like to preserve things, so I want to preserve .bash_history. I would like to copy it into a directory using a script. Like here #!/bin/bash #Something here? number=~/Desktop/Coding/Bash\ ...
3
votes
1answer
676 views

Add content one file to another

FILE1=$1 FILE2=$2 if [ ! -e "$FILE2" ] then touch $FILE2 fi while read line; do if grep -q "$line" $FILE2 then echo else echo $line >> $FILE2 fi done < $FILE1 I want ...
1
vote
1answer
225 views

How to enable yank-nth-arg using vi mode on Bash?

Hey guys I'm trying to figure out how can I take my nth arg, from my last command, without using the !:nth. In a normal bash (emacs mode) I can do that using the follow shortcuts: <ESC>nth_arg ...
3
votes
2answers
2k views

How to call a shell script from Javascript code?

I am not able to call a shell script program from javascript(for example if someone will click a button in webpage then a script will run and will throw some output)???
6
votes
2answers
2k views

How to treat strings with spaces as a whole in bash? [duplicate]

I'd like to build an error handler which will make an empty file marked with the error_occur time. The core idea is to use the result of date command as a parameter. I did: time_stamp=$(date) touch ...
0
votes
1answer
323 views

Grep -m 1 doesn't work

I'm using the following command to parse a form element from HTML using grep. The $RESP variable contains the output from a previous curl request ... echo $RESP | grep -m 1 -o -E 'name="id" ...
1
vote
1answer
441 views

Bash Brace Expansion & Variables [duplicate]

I have a find command: find Directory/{Alpha,Bravo,Charlie} arg1 arg2 I want to replace Alpha,Bravo,Charlie with $find_dir find Directory/{$find_dir} arg1 arg2 however the latter expands to ...
2
votes
2answers
669 views

What do square brackets in bash case statement mean?

http://ss64.com/bash/case.html SHOWS case word in [ [(] pattern [| pattern]...) command-list ;;]... esac What are square brackets indicating? Other websites omit them (i.e. no [[(] etc.) ...
30
votes
1answer
2k views

Why can Shell builtins not be run with capital letters but other commands can?

Why is this? When I do this CD ~/Desktop It doesn't take me to the Desktop. But this: echo "foo bar" | GREP bar gives me: bar
2
votes
1answer
52 views

Fastest way to find whether a file exists in a number of tarballs? [closed]

Is there a more efficient way to do this other than using tar tf and checking the output of every file against the file that I'm looking for? This is the way I do it right now, but it's very slow ...
2
votes
1answer
92 views

why completion does not work for all aliases?

In my .bash_aliases file I have couple of aliases, like -- shopt -s expand_aliases alias emx='emacs' alias em='emacs -nw' alias gv='gvim' alias v='vi' alias ev='evince' when I use them and press ...
4
votes
1answer
732 views

Write the same file multiple times to one file using dd

I am trying to create large dummy files on a drive using dd. I am currently doing this: #!/bin/bash writeFile(){ #$1 - destination directory/filename, $2 - source filepath $3 - blocksize, $4 - ...
4
votes
4answers
381 views

How do I remove every number that's surrounded by <>

I have tried this sed -i '' 's/[0-9]*<>/g' But it didn't work. Example file: <Number1> </Number8> output: <Number> </Number>
4
votes
2answers
458 views

How do I populate end tags using sed, awk or any other command?

I have a txt file that looks like this: <sss>ss< or <firstword>anotherword< I want it to look like this <sss>ss</sss> or ...
1
vote
1answer
406 views

How to grep the logs for a list of patterns and make a report out of it?

I have a C++ executable which scan some of my files and those files has some user id in it. After scanning is completed it generates below log file (abc.log) like this - INFO [0x7faff2b32a00] ...
3
votes
1answer
242 views

Echo out lines of script before running them

Is there a way to run scripts in bash that makes it so that it prints each line of the script before executing it? This would be really useful to me for debugging... $./myscript.sh echo "Hello" ...
0
votes
2answers
132 views

Running Tasks in Parallel using Bash

I am using this script to analyse data. #!/bin/bash inlist=/aut/cl/tera/mja/scripts in=/aut/cl/tera/mja/data/ran_ready/ out=/aut/cl/tera/mja/data/mas/aft/ for i in $(cat $inlist/list.txt); do echo ...
1
vote
3answers
751 views

Pipe/redirect a group of commands

I currently use the following setup to redirect the output of multiple commands: echo "Some normal commands" ( echo "Error: something happened" echo "Warning: this incident will be logged" ) >> ...
0
votes
1answer
90 views

Getting video card product name in terminal

My laptop is equipped with an Intel i5-3317U CPU that, according to this, comes with an Intel® HD Graphics 4000 video card. However, with lspci | grep VGA I get "Intel Corporation 3rd Gen Core ...
-5
votes
1answer
390 views

Extract multiple lines from text file [closed]

Source : ! hostname RTR-1 ! boot-start-marker boot-end-marker ! logging buffered 64000 informational no logging console ! interface FastEthernet0/0 description LAN ip address 172.16.29.250 ...
1
vote
1answer
216 views

I am try to interactively add a user via “useradd”

I am basically trying to write a simple script to allow for interactive use of "useradd" with select options. The options I am trying to allow for specific use are to either be defined interactively ...
33
votes
2answers
3k views

How does `cat <> file` work?

cat < file prints the contents of file to stdout. cat > file reads stdin until Ctrl+D is detected and the input text is written to file. cat <> file, at least in my version of Bash, ...
0
votes
1answer
353 views

Spaces in directory name Bash [duplicate]

I'm new to bash and I'm working on script that traverses the tar.gz file archive and in each file changes a string specified to an another string. Args of script: name of archive, searched string, ...
6
votes
2answers
2k views

Piping bash string manipulation

I've read some other piping bash string manipulation questions but they seem to be specialized applications. Essentially, is there a way to do the below simpler? instead of $ string='hello world'; ...
1
vote
2answers
607 views

How to fix corrupted bash-completion in command substitution?

it seems my bash-completion got corrupted. Every time I try to use command substitution, for example when I type ls $(ls Deskto<Tab> ..result is.. ls $(ls Desktobash unexpected eof while ...