Questions about shell scripts, executable files that are interpreted by a shell (bash, zsh, etc.).

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4
votes
4answers
1k views

Concatenate filename inside of CSV file for each line for multiple CSV files

I have lots of CSV files and I need the filename of each specific CSV file in every line of each file. Original file content of abc123.csv: ColVal_1;ColVal_2;ColVal_3 ColVal_4;ColVal_5;ColVal_6 ...
1
vote
7answers
332 views

Get text between two special characters in a line using shell

I have a line which comes from a file via: cat aaa.txt | grep "HIJK" Output gives: HIJK="My name is HIJK" I need to get the text My name is HIJK into a variable in a shell script. I have tried ...
0
votes
1answer
216 views

How to make xargs ping and head output as expected?

Given an array of domains I would like to obtain their IP addresses, in the following format: 98.139.183.24 98.137.236.24 This script #!/bin/bash domains=(yahoo.com yahoo.ca) printf "%s\0" ...
3
votes
6answers
126 views

Collapse some repeated parts of successive lines

I have data in notepad like this: 4480-1 4480-2 4480-3 4480-15 4581-1 4581-2 4581-3 4581-4 Can we do it using for loop sort of things? With sed? My required output is ...
1
vote
2answers
2k views

list files and store it in variables

im new with shell programming. my goal is to give the user a selection which file should be run. i catch all available scripts in one var with: var=$(find script*) so far so good.. this is the ...
0
votes
0answers
251 views

Find if the file is compressed or not

I need to find whether the file is compressed or not in script.If it is compressed I need to uncompress and send as attachement. My find command results in two files sum12.pdf.Z and sum23.pdf.Z My ...
0
votes
2answers
36 views

names that occur the largest number of times in a data set

users directory ---------------------- hjsyeh hellodir ; awgshd newdir; hjsyeh hidir; jkdhjk welcomedir the above given are set of users and the directories they created .How can I ...
0
votes
2answers
40 views

Output multiple strings out of multiple files

Hi my current code is: find /home/user/logfilesError/ -maxdepth 1 -type f -name "gBatch_*"\ -daystart -mtime -1 -exec grep -rl "ERROR" "{}" + | xargs -l basename if [ $? -eq 0 ]; then ...
1
vote
2answers
110 views

Hiding Script Command Output

I'm building a shell script to automatically configure a specific computer with the best settings. I would like to hide all output from this script except for echo output. Is it possible?
2
votes
2answers
379 views

How to parse multiple string patterns in linux shell script

I am new to linux shell and I had a hard time thinking of the solution to this. Can somebody help how to parse multiple strings (data) in a file? For below file, I want to parse all the values next to ...
6
votes
3answers
250 views

Print a multiline variable in a column

I have a script that collects values from a cluster. The values, in some cases, have multiple lines. I have a printf format that specifies how the data should be positioned however, it doesn't take ...
2
votes
1answer
586 views

What is wrong with this code?

I have a script that goes like this: while : do Start_Time=$(date +"%s") MAIN PROGRAM GOES HERE (CROPPED TO SHORTEN THINGS) Run_Time=$(( $(date +"%s") - $Start_Time )) if [[ ...
1
vote
1answer
132 views

Submitting jobs with sequential completion

If I have numerous jobs that rely on environment variables, how can I submit them sequentially? Here is my attempt that has not been working, week 6 is always submitted (and finishes) before week 5. ...
1
vote
2answers
269 views

Problems with basename in a loop

I am new at shell script programming and I'm trying to execute a software that reads a text and perform it's POS tagging. It requires an input and an output, as can be seen in the execute example: $ ...
2
votes
4answers
369 views

Inserting a line in a file only if this line isn't yet part the file

Total newbie to shell scripting, I am searching to create a script to automatically apply some custom configuration to text based configuration files. In the present case, I am searching to add 2 ...
0
votes
2answers
3k views

Exit the bash function, not the terminal

I have a bash script as below which installs zookeeper but only if not installed already. ##zookeper installZook(){ ZOOK_VERSION="3.4.5" ZOOK_TOOL="zookeeper-${ZOOK_VERSION}" ...
2
votes
3answers
613 views

How to set variables from find+exec?

I am trying to write a bash script where I am trying to find if some location has empty files or not and send an email if found. I first thought about combining "find" and "mail" together, but if the ...
1
vote
1answer
225 views

Identify python script is waiting for a manual input

I'm writing a shell script which executes a Python script. The Python script halts for a manual enter to be provided. However, I don't wan't to have to press enter each time to the script. Instead, I ...
11
votes
7answers
2k views

Shortest way to extract last 3 characters of base (minus suffix) filename

I'm trying to set a variable in an sh script to the last 3 characters of the base name of a file (by base name I mean without the path and without the suffix). I've succeeded in doing this but, purely ...
0
votes
2answers
136 views

UNIX: Submit job only after previous job completes?

I would like to submit the same .sas job iterating over an argument, but I would like job only to be submitted after the previous is completed. Here is my attempt: #!/bin/ksh export weeks="1 ...
4
votes
4answers
234 views

Single instance of script, but only with same arguments

I have this beautiful little code here that will exit from a script if there's another instance of it running: single_instance(){ if pidof -x "${0##*/}" -o %PPID >/dev/null; then exit ...
0
votes
1answer
600 views

How to exit the script in ssh session?

My script contains a ssh command to login to remote server and execute a few commands, The command checks if a file exist and if not it should come out of the entire script. ssh $user@$hostname "if[ ...
9
votes
2answers
4k views

Do parentheses really put the command in a subshell?

From what I've read, putting a command in parentheses should run it in a subshell, similar to running a script. If this is true, how does it see the variable x if x isn't exported? x=1 Running ...
0
votes
2answers
5k views

Passing a variable to a bash script that uses 'EOF' and considers the variable a literal [closed]

in this script i end up with "$1" being saved to the /test file. #!/bin/bash cat > /test << 'EOF' $1 EOF the truth is.. i need to keep 'EOF' as 'EOF' because my argument($1) contains ...
4
votes
6answers
5k views

How to tell “cat” command to not hang on when there is no path provided?

I am simply trying to get a bash script to return the content of a text file. #!/bin/bash cat $1 the problem is.. when the path to a file is not fed to this bash script... how will it even close ...
0
votes
1answer
45 views

script to zip a file and change its owenrship

I have a script I am working on that reads off of a text file and will use the information stored in the text file to put each line entered in as an array. This array is a reference to files that are ...
1
vote
1answer
805 views

Attachment missing in Unix mail when multiple files were attached

I am trying to attach multiple files in Unix, which are the result of a find command. When I try to send the mail, the attachments are missing. dir=$path echo "Entered into $spr/sum_master" for fil ...
0
votes
3answers
478 views

Checking if line in file exist

I have a bash script which asks a user for the number of CPU cores and saves it to variable named $cores. Now I want to add this variable to .bashrc, so I ask user how much CPU cores he has and then ...
2
votes
1answer
210 views

shell script for mounting external device to mount point

I want to make a script to mount an external device to a particular mount point e.g say /mnt. Let me elaborate my question, suppose I run fdisk -l in terminal I would get this output Disk identifier: ...
-2
votes
1answer
50 views

Read file and do below command [closed]

From the 2 different web page the output goes to a single file called "traffic" From one page it always has a string "sqr" and from the other page it does not have the sqr string but "attach" I need ...
1
vote
4answers
2k views

Error: integer expression expected

I have written a script to determine the Load average on the server as follows: #!/bin/bash loadavg=`top -b -n1 | grep -i load | awk -F, '{print$4}'| awk -F: '{print $2}'` if [ "${loadavg}" -le 1 ...
1
vote
1answer
1k views

How to display a .jpg file using fbi in a bash script for set amount of time and then execute the next command in the script

I am trying to use fbi in a bash script to display a series of .jpg images. But once fbi begins its process, it continues to cycle through the images and I only want to display each image once for a ...
2
votes
3answers
261 views

Strange formatting of date in bash script

I am working on a script to sort my downloads folder by the date the files were created. This is the script I am using: #!/bin/bash cd ~/Downloads for FILENAME in * do if [[ -f $FILENAME ]]; ...
-1
votes
2answers
134 views

How to get `expr match` to extract colon-delimited key-value pair?

Given: myvar="present-value: 1", I'd expect expr match "$myvar" '\([0-9]\)' to output 1. However, instead it outputs blank and exits with a non-zero status code indicating no match. How can I get it ...
2
votes
1answer
4k views

Attach files for sending mail which are the result set of find command

By using find command I got multiple files. Now I want to add all these files as mail attachment. Please help me how to add these files as attachment in single mail. I want to implement this in ...
2
votes
2answers
1k views

bash function execution from command line

I love to play with bash script a lot. But I want to enhance the way I use bash script. I have a script(nepleaks.sh) as below used during my programming, ~ 1 clean(){ ...
0
votes
2answers
2k views

How to get the value from rows and columns from text file in bash?

I am working on a bash project. I need to get all the values (one at a time because I will be using them somewhere else) from a text file. The text file I will be getting is structured like this: ...
4
votes
2answers
501 views

Launching a terminal emulator without knowing which ones are installed

I need to write a script that will launch a terminal emulator and run a particular command in it. Since I don't know which terminal emulators have been installed on the target system, how could I find ...
0
votes
5answers
2k views

how to extract part of a filename before '.' or before extension

I have files in format below: abc_asdfjhdsf_dfksfj_12345678.csv hjjhk_hkjh_asd_asd_sd_98765498.csv hgh_nn_25342134.exe I want to get the value before the . and after the last _. The result would ...
3
votes
4answers
1k views

How to cut everthing until a specific word / after a find in a script

Hello I try to get the output of files from today wich contains ERROR. I use this to find the files I want: find /home/user/logfilesError/ -maxdepth 1 -type f -name "gandalf_*"\ -daystart -mtime ...
2
votes
3answers
127 views

Use awk results as parameters to another command

I'm extracting rows from a set of text files with awk. The files look like this: 1000 1 75 1000 2 76 1001 1 76 1001 2 80 I'm searching several directories of these with this ...
-1
votes
3answers
85 views

How can i make usage to print only once

#!/bin/bash usage () { echo "run with 1st argument -mux2 or mux4 or mux8 or default(mux2) or all ( all the 3 mux)" echo "2nd argument -struct or ifs or cases or asgn or ...
3
votes
1answer
224 views

Compose and pipe a gzipped tar archive in one go

I'm trying to come up with an effective way to create a gzipped archive of various system partitions on Android, piping everything out to stdout so as to be able to encrypt it as it comes across via ...
9
votes
4answers
16k views

Difference between ls -l and ll?

I'm relatively new to programming as a whole and some tutorials have been telling me to use ls -l to look at files in a directory and others have been saying ll. I know that ls is a short list, but ...
4
votes
1answer
1k views

Variable scope in while-read-loop on Solaris

Could someone please explain to me why my while loop seems to have an internal scope? I've seen multiple explanations online but they all have to do with pipes. My code has none. The code: ...
3
votes
3answers
1k views

Editing INI-like files with a script

I'm writing a script to automate setting up Puppet agent configuration files in Docker. Basically, I need to ensure that the following section is in /etc/puppet/puppet.conf: [agent] ...
5
votes
1answer
118 views

What else can break if I remove export from a variable?

My problem is that when I started coding my script I encountered several variable scope issues which resulted in the bad habit of exporting almost all my variables. Now that my code has got quite ...
0
votes
1answer
48 views

How can I search for a user account in various sudo related config files?

I'm a scripting newbie...and I would like to search multiple servers for user ss7459 in the following files /etc/sudoers, /etc/sudoers.d/itse, /etc/sudoers.d/dbas and /etc/group. NOTE: The numbers ...
0
votes
1answer
196 views

How do I cat a command file?

I have the output of the crontab -l stored in a file (crontab_file) with no extension. But whenever I try to cat it, I get errors saying command not found for multiple line of the file. Here is the ...
1
vote
1answer
125 views

What priority should I give to a script running on startup?

I 'm running Angstrom distribution on an embedded device. I want to make use of its GPIO expansion ports, that are set to be high on start-up. Below, is the code segment, that releases an expansion ...