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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2answers
36 views

What is the difference between . and the current directory?

I'm trying to copy the current directory as a source. Using full paths gives me the expected behaviour, copying the entire directory into the destination. $ cd /tmp $ mkdir a b $ cd a $ touch 1 2 3 $ ...
1
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2answers
87 views

Full file date (without GNU utilities)

I am trying to obtain the full date (created or modified) of a particular file for passing to another program. I have tried variations of options with the ls command but none provide a full date for ...
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1answer
36 views

How to store a variable that increments by the index?

I'm very new to programming and I was wondering how I could store and print the variables that are being incremented in bash. #!/bin/bash ethcounter=$(ifconfig -a | egrep --count "eth") ...
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1answer
2k views

Deleting Non-empty Directory with smbclient

How can I remove a non-empty directory with smbclient? I have tried the following: 1) rm Result: NT_STATUS_NO_SUCH_FILE listing [dir_path] 2) recurse;rm Result: No Error but also nothing ...
15
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4answers
15k views

How to parse hundred html source code files in shell?

I have a couple of hundred html source code files. I need to extract the contents of a particular <div> element from each of these file so I'm going to write a script to loop through each file. ...
1
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1answer
58 views

how concatenate two commands?

Please can someone help me to concatenate two commands on shell, I'd have the path result and concatenate with the number of column in the first field. EX: #this gives me the path of my path ...
15
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4answers
12k views

How to check if pipe is empty

I have piped line in bash script and want to check if pipe has data, before feeding program Searching I found about test -t 0 but it doesn't work here. Always returns false. So how to be sure that ...
0
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2answers
72 views

Parsing HTTP response with shell

I want to parse below HTTP response but I cannot figure out how to grep the values separately using a single curl request. I need these two output. 1. status_code - (Array of HTTP status codes) 2. ...
0
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2answers
110 views

How to remove a script tag from a text file with sed

I have a number of header.php files that have a malicious script tag contained within them (don't ask). I've written a not-so-elegant shell script to replace these with blank space. I had initially ...
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0answers
14 views

Schedule (Cron) executing tasks based on bash scripts using CronniX

I'm still quite new you Mac and OS X but do have some background about other UNIX based systems, so please excuse for any misunderstandings. My goal is to implement a function that executes certain ...
1
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1answer
23 views

How to Load data to one table from Multiple excel files?

I have to load data from multiple excel file into one table , Please help me to achieve the solution. We are getting excel file from different retail shop which contain multiple column , each file is ...
1
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0answers
22 views

Start a subshell then run commands

Say I have a script that is always run from an interactive shell. I would like this script to launch an interactive subshell that is a replica of the parent (i.e., all environment variables, etc. ...
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0answers
28 views

ssh some commands through (a variable amount of) intermediary hops

(I hope I did search the se sites correctly to avoid duplicates: I did not find a similar question/need, and most similar questions only hop through 1 hop) : the need: I need ideas to create a way to ...
3
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3answers
618 views

Can I hook into the cd command?

I'm trying to set something up on a server I run, when ever I cd into a public_html folder 95% of the time there's a few commands I will always run to check certain things. Is there anyway I can hook ...
4
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2answers
8k views

changing current working dir with a script

I've read this question and answer, but it doesn't quit fit my problem, even tho it's similar. I'm writing a script (called cpj) that will launch one of my current projects. I have about 5 of them. ...
0
votes
1answer
15 views

Getting error while using httpd -v command in script

I wrote a script to check the details of Web server's(RHEL) and save the output into a file. But the script is not passing the command httpd -v in the loop. Here is the script. #!/bin/bash for i in ...
1
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2answers
17 views

Find unique lines based on only a section

I am wondering if there is a way to split lines by some character (E.g. :) and find unique lines based on one part of this split. For example if I had the following piped in via stdin file1: line 4 ...
1
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2answers
60 views

Linux shell that allows you to choose from tab completion

This is an odd question, and I don't have a lot of information to provide but .. I recall seeing a Linux terminal that had a feature which allowed its user to choose between the options listed from a ...
3
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2answers
40 views

wait and recycling of PID

I have a concern whereby in a script, I will be calling parallel versions of a function to run in the background and then issuing a wait. a () { sleep $1 } a 10 & PIDs="$PIDs $!" a 50000 & ...
3
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0answers
56 views

Shell Arithmetic Expansion with Quotes

In Bash and Dash, using quotes in an Arithmetic Expansion is illegal: $ bash -c 'x=123;echo $(("$x"))' bash: "123": syntax error: operand expected (error token is ""123"") $ dash -c 'x=123;echo ...
0
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1answer
37 views

How to replace single quotes and &apos in a file

I am trying to replace single quotes in a file and I used the command as sed /s/'//g filename and this command works fine but I have &apos character also in my file and which is not getting ...
1
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5answers
766 views

Rerunning the same command with a different parameter

I know that I can run the following command ls Some{File,Folder} And it is equivalent to running this: ls SomeFile SomeFolder (I also use it a lot for things like mv place_{a,b}) However, I was ...
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0answers
10 views

adding and removing printers in MAC OS X Yosemite

I work in a school district and using DepoyStudio to remove and add printers on OS X Yosemite. I've tested both shell scripts in terminal and they work and when I use deploystudio workflow it runs ...
8
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6answers
5k views

How to rsync files between two remotes?

I would like to transfer files between two remote hosts using on local shell, but it seems rsync doesn't support synchronisation if two remotes are specified as follow: $ rsync -vuar host1:/var/www ...
3
votes
1answer
30 views

What is the purpose of the uucico shell on HP-UX, Solaris, and possibly other Unix varieties?

For my work, I review Unix and Linux server configurations for compliance with security guidelines. So I'm not a Unix admin myself, but I work with Unix servers on a regular basis and am fairly ...
0
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1answer
18 views

bash-like last command in history using up-down arrow keys in zsh [duplicate]

In bash, we can use the up and down arrow keys to get the last or nth previous command in history. Can we do this in zsh?
8
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4answers
176 views

dirname and basename vs parameter expansion

Is there any objective reason to prefer one form to the other? Performance, reliability, portability? filename=/some/long/path/to/a_file parentdir_v1="${filename%/*}" parentdir_v2="$(dirname ...
2
votes
2answers
55 views

Set awk array on command line?

I know the -v switch can be used to awk on the command line to set the value for a variable. Is there any way to set values for awk associative array elements on the command line? Something like: ...
9
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2answers
515 views

Shell namespaces

Is there a way to source a shell script into a namespace, preferably a bash shell script but I would look into other shells if they had this feature and bash didn't. What I mean by that is, e.g., ...
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0answers
12 views

List all files in USB device from /Volumes shell script [duplicate]

To clear things up I have setup folder actions on my mac for whenever a USB device is plugged into my mac it will run a shell script. When I list all files in the Directory /Volumes i get $ ls -a . ...
6
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3answers
12k views

Case-insensitive substring search in a shell script [closed]

How can I write bash code that will do a case-insensitive substring match of command output?
5
votes
5answers
17k views

How to catch an error in a linux bash script?

I made the following script: # !/bin/bash # OUTPUT-COLORING red='\e[0;31m' green='\e[0;32m' NC='\e[0m' # No Color # FUNCTIONS # directoryExists - Does the directory exist? function directoryExists ...
8
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1answer
419 views

How to find out whether a shell script is written in bash or sh

How can I find out whether a script is written in bash or sh? The first line of the script is not helpful here, since on Linux, bash scripts have this line: #!bin/sh Actually, there are many ...
11
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3answers
974 views

Why does set -e not work inside () ||

I've run across some scripting like this recently: ( set -e ; do-stuff; do-more-stuff; ) || echo failed This looks fine to me, but it does not work! The set -e does not apply, when you add the ||. ...
0
votes
1answer
23 views

regarding recursive deleting of a specific file type

I wanted to delete a specific file type say *.bak file from any directory and its subdirectories. I used the following command to find the files. find <path> -name "*.bak" -type f However, ...
77
votes
30answers
22k views

Quick directory navigation in the terminal

I would like to frequently switch between directories that are in totally unrelated paths, for example /Project/Warnest/docs/ and ~/Dropbox/Projects/ds/test/. But I don't want to type cd ...
0
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3answers
41 views

How to put variable in for loops? [duplicate]

for seq in {046725..046899} do #body done Above segment of code runs beautifully keeping preceding zeroes in seq variable but why following code segment doesn't run? Is there any way? I need seq ...
3
votes
3answers
171 views

move middle part of filename to front

I have files named in the style 02.04.11 DJ Kilbot.mp3 (for several dates) and I want to reformat the name in this manner: DJ Kilbot 2011-02-04.mp3. In other words, the current format is MM.DD.YY ...
3
votes
3answers
42 views

How to treat numbers starting with zeroes as decimal integer

Input would be file name like following : A-B-000001-C A-B-000002-C ..... ..... A-B-999999-C All file should be sequential. I want to find missing sequential file names. For this I'm separating 6 ...
1
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3answers
36 views

What does the option -9 mean for killall?

I saw the command killall -9 but there is not such a option in the man page. So now I'm a bit confused: what does -9 option mean?
33
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1answer
3k views

Does 'rm .*' ever delete the parent directory?

The expression .* is expanded by bash to include the current and parent directories: $ ls -la total 2600 drwxrwxrwx 2 terdon terdon 2162688 Sep 10 16:22 . drwxr-xr-x 142 terdon terdon 491520 Sep ...
0
votes
1answer
29 views

Kill process with timeout

I want to start a programm with timeout, how can I kill the process using SIGINT and SIGKILL? If the programm not terminate within 5 seconds, send SIGINT. If it’s still running after 10 seconds (in ...
0
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2answers
35 views

Use a shell variable with Awk

I have this: if [[ $1 = "-c" ]] && [[ $2 =~ ^[a-z A-Z]+$ ]] then awk -v var="$2" '{print $2}' something.txt fi What I want is with a comand like -c abc to show the lines in something.txt ...
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votes
1answer
29 views

How is a trace of commands different from shell input lines?

I am unclear about two options when invoking a bash shell process or for set: -v Print shell input lines as they are read. -x Print a trace of simple commands, for commands, case commands, ...
0
votes
1answer
36 views

Get the external IP address in shell without dig in 2016?

This question: "How can I get my external IP address in bash?" Solves the question with a call to dig: dig +short myip.opendns.com @resolver1.opendns.com; that is the fastest resolution possible, ...
56
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9answers
93k views

How can I get the size of a file in a bash script?

How can I get the size of a file in a bash script? How do I assign this to a bash variable so I can use it later?
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4answers
1k views

How to subtract two times in shell

I nee to subtract two lines which is in the format of time in shell. The time format is hh:mm:ss I used the code below to get the time. cat /var/log/kern.log |grep usb |tail -2| awk '{print $3}' ...
0
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1answer
20 views

How to set up a pre-defined variable with multiple directory paths to use with the find command

I am looking to have a script delete files that are older than 90 days in certain directories. As in, there are 8 directories that have different paths to them. I can run the find command on one ...
0
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1answer
32 views

Parenthesis on echo shell command

I have this echo command: $ echo "alias notepad++="C:/Program\ Files\ "(x86)"/Notepad++/Notepad++.exe"" >> ~/.bashrc As shown in the picture it does not recognize the parenthesis.
0
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1answer
1k views

openSuse, not running the cron job

I have created a cron job in the /etc/cron.d/dispatchingEmail_I the permissions of dispatchingEmail_I are the following: -rw-r--r-- 1 root root 84 Sep 11 19:52 dispatchingEmail_I content of ...