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

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0
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21 views

This code isn't working. (Trying to declare array values in a for loop and do math functions on them)

I was again bored and looked up a list of programs to make in bash, and I'm trying to make a CC (credit card) validator. I had to split the characters into an array to do the validation, and I think I ...
1
vote
0answers
19 views

Exceeding paste's length limits in resulting line? [on hold]

I'm in a situation where I am extracting files using Informatica.My problem is that in extreme cases I'm exceeding the maximum length for a resulting line for the header line. I'm on Oracle. What I ...
-1
votes
1answer
45 views

Pass string value to date in Unix

mm="27 Jun 2011" dd=$(date -d'27 Jun 2011' +%Y%m%d) echo $dd I want to use value of mm in second line. When i tried like below dd=$(date -d'$mm' +%Y%m%d) It is giving error.
3
votes
1answer
44 views

Script started as `source` or `executable`?

Can we determine inside the very script whether it started as source (.) or executable (shebang or something alike)?
0
votes
1answer
22 views

Export mysql to remote server using one SSH session

I've come across a situation where I had to create a utilitary shell script that would be executed in many servers from different regions. The objective is to dump the local mysql database, copy it to ...
0
votes
0answers
50 views

comma and newline to be replaced with comma [on hold]

Can anyone help me finding the solution to replace comma and newline with comma, below is the sample format. www_sngforadultadhd_com, www_scegforadultadhd_com, www_scegforadultadhd_com, ...
0
votes
2answers
65 views

What is wrong with the code? [on hold]

#!/bin/bash for ((i=1 ;i<=3;i++)) do echo "Enter gallon used(gal):" read gal echo "Enter Miles Obtained(mil):" read mil mileage=`echo $mil / $gal |bc` echo "scale=4; $mileage " | bc c=`echo $c + ...
0
votes
3answers
43 views

Bash: increment a variable in a while loop?

Bash newbie here! I have a bash script that for each file in a set, greps each line in the file for a string. Then it splits the line on commas, converts the 7th element to a float, and increments a ...
-1
votes
1answer
26 views

shell script not running using crontab

This is my script mboxutil -l > n.txt sed 's/^.*user//' n.txt > n1.txt cat n1.txt | sed 's/^.//' > n2.txt sed 's/\/.*//' n2.txt > dss_list.txt rm -f n.txt rm -f n1.txt rm -f n2.txt sed ...
0
votes
1answer
29 views

How to extract particular fields from lines using shell commands?

File1: 27/07/2014 10.10.03 Breaker1 was closed by Mr. A.Basu Spectrum ui6dms 29/07/2014 04.50.53 Breaker1 was opened by Mr. D.Gupta Spectrum ui6dms and one note added 30/08/2014 03.20.01 EarthSwitch ...
6
votes
3answers
258 views

Should I use a slash at the end of path variables in shell script or not? [on hold]

Today when writing my shell script. A question suddenly comes to my mind. Since cd /target_dir and cd /target_dir/ both works. Should I add a slash at the end of my path variables in a shell script? ...
3
votes
1answer
615 views

KSH styling text based menu using STDERR

Is it possible to format the STDERR in order to have a better looking menu using the select command? I have a simple select select oChoice in $(<tempMenu.menu) ; do case "$oChoice" in ...
-1
votes
1answer
82 views

mv command does not work in shell script [closed]

I want to rename a folder with a bash-script. I don't know why this command is not working in a shell script, but directly in the terminal is working without problems. ...some code... ...
-3
votes
1answer
38 views

sed/awk - replace first occurance of a string with array of strings [on hold]

I want to find the first occurrence of a word and replace it by 3 strings using sed/awk. for example , I have the below entry in my /etc/hosts file 10.4.16.11 dispatch1 10.4.16.12 dispatch2 ...
0
votes
2answers
230 views

init.d script not being run on boot

My script is not running on boot in a vagrant box under Ubuntu. My script looks like this - #!/bin/bash # /etc/init.d/mailcatcher ### BEGIN INIT INFO # Provides: scriptname # Required-Start: ...
3
votes
2answers
54 views

Script for changing modification time of files and directories recursively

I have many big folders with thousands of files in them and I want to use touchto set their modification times to be "original time"+3 hours. I got this script from a similar thread in superuser: ...
53
votes
2answers
1k views

Security implications of forgetting to quote a variable in bash/POSIX shells

If you've been following unix.stackexchange.com for a while, you should hopefully know by now that leaving a variable unquoted in list context (as in echo $var) in Bourne/POSIX shells (zsh being the ...
2
votes
3answers
199 views

Am I using a while loop wrong?

I found a list of projects to do, and one of them was something that generates amounts of change. I made this code: getamt() { echo "Enter amount of money." read amount echo "OK." } change() { ...
4
votes
4answers
96 views

How to Check the existence of multiple files in a directory and zip the same

I am facing an issue while checking the existence of files ending with the same string/pattern. The file names might be as follows abs_123.unl xyz_123.unl Currently my code is as below and working ...
0
votes
3answers
53 views

Creating a script that runs a simple command for all files in a directory

I need to use the text-based browser Lynx to dump 1000s of html files into text files, with the same filename. For any given filename.html the command is lynx filename.html --force-html --dump > ...
1
vote
1answer
36 views

CasperJS and PHP In Cron Job Cannot Open Files, Works Fine When Run Manualy

I recently got a new DigitalOcean LEMP environment with Ubuntu. I tried making an SH script that uses CasperJS to scrape data from an external website to a JSON file, and a PHP script to parse the ...
0
votes
2answers
39 views

validate record count in header

I am trying to write a script that should verify total detail records equal to the Record_count in header record, If not throw an error sample data 0001 HD SAP _AP Distribution 20150615 131723 ...
0
votes
1answer
15 views

Substituting the value with spaces for a variable in bash script - the correct way

I have a compilation script that can compile the program with and without the debug symbols. I want to ask via bash prompt ( read ) the user to choose whether he wants a debug version or not with ...
3
votes
1answer
168 views

Approximating a floating point number with correct rounding off

How can I approximate a floating point number using shell-script (say, up to 4 digits after the decimal point)? I have two examples: A=1.2345678 and B=1.2345678E-05. So I would like to get ...
1
vote
1answer
41 views

Syntax error at a semicolon in a shell script

The one liner command will be longer but this is the part that is throwing the error. for user in natural1 ; do cat <<EOT >> /home/$user/public_html/.htaccess <FilesMatch ...
11
votes
10answers
8k views

Decoding URL encoding (percent encoding)

I want to decode URL encoding, is there any built-in tool for doing this or could anyone provide me with a sed code that will do this? I did search a bit through unix.stackexchange.com and on the ...
-2
votes
1answer
37 views

Comma and newline replaced with comma [duplicate]

How can I find the solution to replace ":" and newline with comma, and to remove "./" below is the sample format. ls -lRm ./www.toncemoy.com: www_ttoncemly_com, www_ttoncely_com, www_toncethly_com, ...
1
vote
2answers
30 views

How to preprocess CUPS' `lp` with a script for a specific printer?

(How) Is it possible to preprocess lp automatically with a script? Piping inbetween (fileToPrint | script.sh | lp -d myPrinter) is no option for me, because I have a lot of source code that does lp ...
0
votes
1answer
34 views

How remove duplicates in same file and with if condition?

INPUT FILE: has all these values without header: customer ID, code, start_date, end_date 124343, DCW, 2015-07-06, 2016-08-03 235432, ABC, 2015-04-26, NULL 235432, ABC, ...
1
vote
6answers
159 views

Hiding Password in Shell Scripts

How can I hide a password in shell scripts? There are a number of scripts that are accessing database. If we open the script others also aware the username and password. So if anyone knows how to hide ...
1
vote
1answer
26 views

Silent installation of shell script using bash file [on hold]

I have a setup file for Linux which is in shell script format. I'm trying to perform a silent installation by writing a bash script. When I directly access the script I'm unable to suppress the setup ...
4
votes
6answers
167 views

Append something to each list in a file

I have a file, lists.txt, that looks like this: // stuff at beginning of file var list1 = new Array(); i = 0; list1[i++] = 'a'; list1[i++] = 'b'; ... list1[i++] = 'z'; var list2 = new Array(); i = ...
-3
votes
0answers
52 views

Bash Shell - Grep a line from a file - append from an entered variable and query that line?

I would like to grep a line from a txt file use that line and append the variable used "entered from the user. Get the output of the grep add variable with a space and then query that line. Any ...
0
votes
1answer
43 views

Practical usage of “shift” shell builtin command?

I checked the /usr/bin/ssh-copy-id(part of openssh-client package at least under Debian) shell-script and it contains following if-statement: if [ "-i" = "$1" ]; then shift # check if we have 2 ...
-1
votes
2answers
35 views

Enter a variable into a command in bash

My question should be simple for you guys. I am writing a simple script that runs a command but the file it would need is always different. Is there a way for it to ask: "Where is the file?" And ...
-1
votes
2answers
14 views

OpenDNS automatic diagnostic

I've contacted OpenDNS support because advertising are not filtered on this site http://www.backpackerboard.co.nz/ They asked me to read this manual instructions ...
1
vote
1answer
51 views

Can someone explain this tail + line to me?

I'm looking through some of the scripts that are on the servers and came across an 80MB shell script. Naturally curious I decided to look in there and came across this line: tail +4802 $0 | zcat - | ...
0
votes
2answers
30 views

generate alphanumeric string from pattern

I want to generate host names for example from my patter like this: inc-[tnc][app|web][1-10] where it should output like below: inc-tapp1 inc-tapp2 . . inc-tapp10 inc-napp1 . . inc-capp10 inc-tweb1 . ...
1
vote
2answers
53 views

How do i search for certain sections of a file and then extract only relevant information within that section?

So I have a text file that is a server report and has about 1000 lines of information in it. I'm trying to write a script that can search the report for only certain pieces of information I'm looking ...
9
votes
6answers
1k views

Is it possible to substitute “then” with brackets?

I first learned how to code in a C language, and using if ( code ) then code fi makes it really hard for me to read my code (don't ask why). Is there a substitute for then? Something like this: ...
2
votes
4answers
120 views

How to see if there are any matching characters in a string?

I'm making a card hand generator, and I want it to note if a specific hand is generated, like a three of a kind or a full house. I was trying to figure out how to do it, and I thought of using grep on ...
2
votes
1answer
104 views

'Tar' the result of a 'find', preserving the directory structure

I want to tar all the *.txt files that I get as the result of a find command, that exist in a directory having a tree structure like this: Directory_name dir1 file1.pdf file1.txt dir2 ...
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votes
2answers
37 views

Transform text records using only a “for” loop

I have an input file that is text, consisting of lines that look like: 352|C|PAID|7036|VOICE|01-FEB-12 I need to split each line into fields at the | (vertical bar) characters and output each field ...
0
votes
1answer
32 views

Is it bad practice to put sections of main code in functions? [closed]

I didn't like the way the code that I had looked, so I compressed all of the main 'blocks' into functions. (This would also prevent the code from running if an error was present.) I don't know if this ...
3
votes
2answers
106 views

When GNU parallel exit,my program also fail

I am using GNU parallel to run a bash function. The function just contains the bash script to restart my program. At first, the restart is ok, but when parallel exits, my program also fails. Why? ...
0
votes
1answer
52 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, ...
-1
votes
0answers
17 views

sql query not returning records from DB having timestamp in where clause in shell scripting [closed]

I am trying to get the records from DB using shell script having timestamp in the where clause, but the query is not returning any records. Its shows as "no records found". But the same query is ...
2
votes
7answers
168 views

Restart firewall from bash file

I need to restart firewall periodically, so I created a bash file to add it to CRON tables. In terminal, I restart firewall using command: service firewall restart but if I have similar line in ...
0
votes
1answer
17 views

Comparing Oracle version in bash script

I'm trying to create a bash script to install an application that requires Oracle 11g client. How can I read in the version info within the bash script? sqlplus when run in Putty spits out the ...
0
votes
0answers
22 views

Run a command stored in a variable [duplicate]

I am working on updating some scripts we have used previously ( on RHEL) to work for a new flavor of Linux (ESX). As I am modifying the script, I wanted to add user feedback as well as some other ...