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, …).

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How are long command lines ( > $COLUMNS ) automatically wrapped to a new line?

There are several points where I/O is passed through, some of which (to my knowledge) are the shell, pty, tty, termios, terminal emulator application. In most terminal emulators, long command lines ...
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2answers
85 views

check if a variable is in list

to check if a word is in a list of words or no I wrote this script: tr -s '[[:blank:]]' '\n' < t.txt | while IFS= read -r word; do if [[ "$word" =~ $(echo ^\($(paste -sd'|' ./champs.txt)\)$) ...
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1answer
45 views

Given a *nix command, how do I find where the executable is? [duplicate]

There is a command written in bash I found from documentation from people who previously worked in this project. Now I need to locate the command's source and modify it. I tried which my_command ...
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2answers
47 views

How to search recursively in a directory for different files?

I have a x.tar file in directory /a. After untaring x.tar I got the following result: cust/ cust/01/ cust/01/INFENG/ cust/01/INFENG/scr/ cust/01/INFENG/scr/test.scr cust/01/INFENG/SQL/ ...
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2answers
476 views

How can I make xargs play nice with stdin?

$ seq 1 3 1 2 3 $ seq 1 3 | xargs echo 1 2 3 $ Mentally replace seq 1 3 with any command that lists entries one-per-line on standard out. How can I get more-or-less what you'd expect, i.e. the ...
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4answers
254 views

Change the time zone of a cronjob

I have a cronjob which is executes every day at 9:00 AM of UTC-Time. I'm in GMT+1 so it executes at 10:00 AM local time. When there is the timezone change (to daylight saving time, DST), the cronjob ...
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3answers
141 views

Bash long string, no word splitting?

I want to tidy up some script with long commands, so that for example: { somecheck || somecomand "reallyreallyreallyreallyreallyreallylongstring" } &> /dev/null & becomes something like: ...
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0answers
23 views

What Does the Output of “--help” Mean? [duplicate]

When using the --help option of a terminal program, a lot of output is produced. It usually starts with Usage: and then a bunch of things and brackets and parentheses. My question is, what doe the ...
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1answer
120 views

chrome os: crosh tab completion

Tab-completion doesn't seem to work in crosh, or even in other Chrome OS apps - it kind of does what's expected, in that it tabs to the address bar, but unfortunately that's not what I want. I could ...
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3answers
105 views

bash: error handling on find -exec

I was using this little script to find malformed images: find -name '*.jpg' -exec identify -format "%f\n" {} \; 2>errors.txt It worked well enough, but now I need to modify it slightly. Instead ...
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0answers
48 views

Counting program fails in arithmetic test

having a little trouble with this rather basic script. This script works on Bash in my macbook pro, but not on my Linux Mint desktop, which also uses bash. I can't figure out what's wrong with it, ...
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1answer
53 views

Bash - Command substitution adds single quotes

I have a problem with bash behavior while evaluating grave accents. I want to run find with optional -name: find -name "*.log" works fine, but when i want to get the -name part from nested script ...
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1answer
54 views

Print file name,Modified Date and Size with Header

How do I print file size, file name and modified date with header.Till now I have come up with: find . -regex '.*\.csv' -execdir stat --printf '%n,%y,%s' {} \; How to add header and do not print ...
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1answer
64 views

Running some parts of a script as an unprivileged user with shell environment

I am creating an instance configuration script that sets up a machine. I am running the script via sudo i.e. sudo run.sh. Most of the steps require root access but some of the script's steps do no ...
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4answers
57 views

Sed substitution grouping is appending in OSX rather than the expected sub in Linux

I've got three comma separated columns. Last name, First name, social. I'm trying to capitalize all characters in the last name column using sed 's/\([^,]*\)/\U\1/' foo.file In osx this command ...
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1answer
46 views

Syntax When Combining dd and pv

I am a linux newbie; so, sorry if this is obvious to you... sudo dd if=/dev/sda bs=64k | pv --size 1.5t | dd of=/dev/sdb Does the block size for dd go on the left side of this after the input as ...
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1answer
143 views

Sqlplus: Command not found

I have two virtual machines ubuntu, one is a server when I installed oracle 11g express, and the other is a simple client. My goal is to run an sql query remotely from the client machine. So I ...
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1answer
56 views

How to recover a shell script I deleted from a specific folder in Debian 7?

So in a merry mood last night, I deleted an important shell script from my system. I mistook it for something else and figured it wasn't needed. I am trying to recover it. I have tried 'scalpel' and ...
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0answers
12 views

What shell extension recommends packages if command is not found and how to update it? [duplicate]

I know this question might sound a little strange but i really don't know how to describe it better. On my Debian system I have a shell extension for bash that, whenever I enter an unknown command, ...
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2answers
34 views

Problem with using expr

I've got two strings str1="( 1 + 2 + 3 + 4 + 5 ) / 3 + 5" and str2="( 1 + 2 + 3 + 4 + 5 ) / 3 + 5 * 2" The command result=` expr $str1` returns a correct value, while result=` expr $str2` ...
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2answers
42 views

Background processes mix up order of shell script execution

Can someone explain me why the script echo one && echo two & echo three && echo four gives me [1] 3692 three four one two [1]+ Done echo one && ...
4
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2answers
129 views

My /var/log/ is mysteriously filling up GBs in minutes! Any cure before I re-install Debian 7?

Good morning, fellow *nix enthusiasts! I have been using Debian 7 for a while now and after a recent upgrade I noticed I constantly kept running out space on my root partition. I mean to the point ...
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2answers
809 views

find(1): how is the star wildcard implemented for it to fail on some filenames?

In a file system where filenames are in UTF-8, I have a file with a faulty name; it is displayed as: D�sinstaller, actual name according to zsh: D$'\351'sinstaller, Latin1 for Désinstaller, itself a ...
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0answers
24 views

Is there a way to add a timestamp to the logs for qsub job?

I'm submitting jobs on a cluster via qsub but the error/output logs don't have a timestamp, making debugging more difficult. Is there a way to add timestamps to the logs in the bash script? Appreciate ...
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1answer
66 views

Running every command through another

I'm setting up a system in which any external command that does something with real effect must be crypthographically signed before before the system will execute them. The restrictions are in place ...
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3answers
60 views

copy the contents of a variable in a text file

I know this is a stupid question but I want to know how I can put the contents of a variable in a text file. This variable is a string that I want the code with the base64 command.But this command ...
0
votes
5answers
141 views

Read File word by word

My problem is to read a text file word by word and recovers every word in a variable. I tried to do: while read ligne; do { for ( i=1; i<= length ($ligne); i++); do { var=$(awk '{print $i}' ...
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2answers
30 views

VNC/SSH: How to execute a command after logging in?

I'm looking for a way to create a VNC console user that executes the command screen or bash immediately after logging in so they get their own restricted shell for executing commands etc. Screen/bash ...
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1answer
45 views

Replace mutiple strings with different values in a file using unix [duplicate]

I have a file in which the data is like below, 01,0000000,xxxxxxx/ 02,xxxxxxxx,yyyyyy/ 03,test1,41203016,,/ 01,0000000,xxxxxxx/ ...
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1answer
53 views

shell script for date checking between two days

There is date in my file, like 30-apr-2015. How can I compare this with the current date and get notified if they are equal?
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5answers
49 views

I want to design a scipt to send alert for Swap usage more than 85%

cat /proc/meminfo | grep Swap SwapCached: 460248 kB SwapTotal: 8388600 kB SwapFree: 1031900 kB I want to use this information to compare it with a threshold ...
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4answers
207 views

How to 'drop' characters from in front of a string?

I have a string that I would like to manipulate. The string is H08W2345678 how would I be able to manipulate it so the output is just W2345678? Similarly if the I wanted to drop the last 4 ...
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1answer
44 views

What is the email matching regex in basic regex for grep?

I created a text file and put some email addresses in it. Then I used grep to find them. Indeed it worked: # pattern="^[a-zA-Z0-9]+@[a-zA-Z0-9]+\.[a-z]{2,}" # grep -E $pattern regexfile but only as ...
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2answers
161 views

Why can't I load modules while executing my bash script, but only when sourcing it?

I am using modules to control the packages on my system and I have python/2.7.2 installed as a module. I have simple python executable python_exe.py which I am going to call from a simple 'driving' ...
0
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1answer
85 views

grep: Syntax error near unexpected token `('

I have this problem: I'm looking for a string inside file . Syntax is: grep -E ‘( ^ | [[:space:]] )[A-Z]{2}[[:digit:]]{2}((- | [[:space:]] )[[:alnum:]]{4}) {3} ’ (filename) When I run this ...
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2answers
99 views

Finding files that contain multiple strings

I am trying to find scripts that contain common malicious code, I need to match multiple strings within each file. What I am using is working but am not sure why I get the following in the output: # ...
1
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1answer
49 views

Rsync Excludes Folders

I am running a rsync script and I want to exclude certain folders. I know with rsync you have to create a .txt file and add all the excludes in there but I am wondering is it possible to just have a ...
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0answers
61 views

How to implement command history in Linux terminal?

I am using Putty as Terminal to connect a Linux server running Oracle Linux. To use a command multiple times, I have to type that command each time. There is no function of Up and Down button unlike ...
2
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1answer
97 views

About executing shell script

Suppose I have a shell script file foo.sh. I can do chmod + x foo.sh and change it into an executable file. In Kernighan-Pike: Unix Programming Environment (UP) they show that after this typing ...
1
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1answer
71 views

Output different lines when comparing two files

I have two text files with the same number of newline terminated strings. The lines in the two files correspond to each other. The lines in each file individually might be repeated. I would like to ...
0
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2answers
51 views

Run script on non-full bash-login invoked as “sh”

Good day I'm currently trying to modify my terminal to have the prompt displayed in a different colour than the whole rest of the shell, and I would like to make it white for normal users and red for ...
0
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1answer
38 views

shell sleep until next full minute

To execute a script on the next full minute I want to tell the sleep command to sleep until the next full minute. How can I do this?
0
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0answers
27 views

Moving Informatica data(directories) from one unix server to another unix server

Can we migrate directories from one unix server to another unix server, without the need of installation of Informatica softwares on the new unix server? If yes, then will there be any change in the ...
0
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4answers
68 views

How to remove line based on Delimeter in perl / Shell?

Can anyone help to remove the line in file based on delimeter(Comma), Incase if line contain less number of columns or Bad records , Need to delete those. Input File: a,b,c,d a,b,d,f c,d a,v,b,h ...
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1answer
64 views

Some commands not working in bash script

I'm using Ubuntu 14.04.02 32bit. On doing some shell programming, I found out that running the script through the sh command sometimes cause errors. Is it because the sh command is invoking the ...
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2answers
71 views

echo $HOSTNAME result become key to a variable

Property server1=abc,def,ghc server2=xyz,tes,iuy #!/bin/sh echo $server1 abc,def,ghc echo $HOSTNAME server1 with those info above, I want to output the output "abc,def,ghc" in a test variable. ...
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1answer
50 views

Relation between system calls and shell commands/utilities

In POSIX, Does a system call function often but not always have a command or utility in shell? Is there some rule of thumb about what kinds of system calls have corresponding commands or utilities ...
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2answers
92 views

Recursively remove files with idx > 10,000

The problem In the current working directory I have several (very many) folders and some of them have lots (like 100,000+) of files inside. My goal is getting just the folder with 10,000+ files and ...
4
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1answer
80 views

Source Bash automatically in terminal

How can I automatically source a particular bash script when I open a terminal window by right clicking somewhere and choosing "open in terminal"? For example, every time I open a terminal I need to ...
2
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4answers
145 views

How can I find the program I'm hiding in bash

Say I have PATH="home/bob/bin:/usr/bin". I am writing a bash script /home/bob/bin/foo that will do some munging and then call /usr/bin/foo. Of course I want to be able to use this script on ...