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

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-2
votes
1answer
92 views

Shell script curl limit the try time for page not found

I found following code to check web url. if curl --output /dev/null --silent --head --fail "$url"; then echo "URL exists: $url" else echo "URL does not exist: $url" fi Here if the page not ...
0
votes
1answer
67 views

Shell script for logrotating

I want to create a shell script for logrotating. following are my requirement. want to archive the log files to a particular directory lets(/usr/local/jboss-5.10..GA/server/archive/log) older than ...
2
votes
1answer
163 views

Huge delay in script response when using SFTP with expect

I am using a script to call SFTP service to fetch some logs from the remote server. This works fine in normal scenario but, i have noticed a very long delay of around 30 minutes or more in some of the ...
5
votes
3answers
655 views

For loop formatting

I am having trouble formatting nested for loops for long strings of input: I am currently using the below nested for loops to name output files from a separate program that I have omitted: ...
3
votes
2answers
332 views

Subtract floating numbers in shell script

I'm trying to do some calculation in shell script with CPU usage. Which return floating point number. But when I subtract this number I'm getting error. See the following code and error. Code ...
1
vote
3answers
235 views

change of date format in awk command

I have a file mdn.txt with following sample record. mdn.txt: 123456,2711448,1,20150214092425,20150714092425,120,20150814163821,,123,,,123,20150214092425,,123,,,123,20150214092425,,123,Y Now I want ...
0
votes
2answers
57 views

Monitor a logfile and execute different commands depending on different conditions

I have a logfile which I want to monitor and depending on which condition is met, different commands should be executed. I found a solution that comes close to this here. Unfortunately it doesn't ...
0
votes
2answers
121 views

Search the value from a dynamic file and pass to a variable in HTML [closed]

I have the following file below with the format and I want to pass the value to HTML BE64533-A0E1-4F98-A91F-02C1D0 column=ABC_Received:ABC_Structure_Type, timestamp=1439978656596, **value=ASCII** ...
3
votes
1answer
4k views

Shell script error (: not found [No such file or directory]) [duplicate]

I'm using following script on linux server. And which is giving: : not found [No such file or directory] This is the script: # ------------------------------------------------------------------ # ...
2
votes
1answer
217 views

n-factor SSH authentication for CentOS 7

How can I enable (and require) n-factor authentication for all SSH connections to a CentOS 7 server? I have read about Google Authenticator, which provides two factor authentication. But that is ...
1
vote
2answers
65 views

How to subtract lines, in reverse, only if greater than previous line

I am working on a shell script that will read the lines of a file, in reverse. I need it to subtract the previous line from the latter, but only if the latter is larger. If it's smaller, then I just ...
1
vote
1answer
87 views

How to use sed to replace keys in a file using a regex?

I would like to modify a file to replace keys, suppose these keys are in the file as: 42NM 52NM 23NO XNNM I would like to replace anything with NM, with the word "Okay". 1 #!bin/bash/ 2 3 if [ ...
-3
votes
1answer
52 views

bash error: Missing '))' [closed]

#!/bin/sh echo "welcome to salary calculator" echo "Enter basic salary" read basic dp=$(( basic / 2 )) da=$((( basic + dp ) * 35) / 100) hra=$((( basic + dp ) * 8 )/ 100) ma=$((( basic + dp ) * 8 ) / ...
1
vote
1answer
54 views

printing in awk

I have a file number.txt with following record. Number.txt: 123456,2711448,1,14-Feb-15 09:24:25,14-Jul-15 09:24:25,120,20150814163821,13-Aug-15 09:24:25,,,12-Sep-15 09:24:25,,,12-Oct-15 ...
1
vote
2answers
186 views

Extract one file from multiple zip files

I have a folder tree which contains multiple .zip folders (approx 600) each containing four files. I wish to extract just one file from each folder and copy it out to a separate folder. To complicate ...
0
votes
3answers
81 views

find command behaviour inside for loop

I have following part of code inside bash script. for dir in $(find /etc/aaa -type d -maxdepth 1) do #my code done #my code if /etc/aaa directory is not present then i want to exit script with ...
2
votes
3answers
104 views

Grab the last executed command from history as a string and store in variable in bash

I'm trying to grab the last executed command, with options, and store it as a string to be written to a file. I've tried using fc but that can only give me the next to last command (for me anyways) ...
1
vote
3answers
76 views

Process text file - Extract data starting with number

I have a list of contact information I need to process in .txt format seperated by , . We only want to keep SIC codes that start with 65 which is real estate. The command should only check for the ...
10
votes
6answers
615 views

Remove lines from a file depending on lines found in another file

File file1.txt contains lines like: /api/purchase/<hash>/index.html For example: /api/purchase/12ab09f46/index.html File file2.csv contains lines like: <hash>,timestamp,ip_address ...
2
votes
4answers
86 views

zsh: map command to array

suppose you have an array a=(foo 'bar baz') is there a more obvious way to apply a command/function to every array element and save the resulting strings into another array than this: b=() for e in ...
2
votes
2answers
192 views

Batch rename according to number of pages in pdf file

I have a lot of papers in pdf files (and also other type of files in the same folder). I'd like to rename them using the pattern <current file name>[<number of pages>].pdf But after ...
0
votes
1answer
74 views

Combining the if-else-if condition to a logical expression

Is the following expression correct way to combine the if-else if statement? if [ $TO_MAJOR -eq 7 ] ; then if [ $TO_MINOR -eq 3 -a $TO_PATCH -lt 2 ]; then echo "AE port not supported" ...
6
votes
2answers
1k views

Get the date of last month's last day in a shell script

How do I get the previous month end date, based on processing date? Examples: Processing date = 15jan2015 Expected date = 31dec2014, Processing date = 10feb2015 Expected date = 31jan2015
0
votes
3answers
192 views

Store CPU utilization into CSV file

OS: Debian 8 x64 I'd like to log every 5 seconds the CPU percentage into a CSV file in the format below: YYYY-MM-DD HH:MM:SS,CPU% I'm not familiar with how to use the top program to calculate the ...
2
votes
2answers
156 views

Find differences in file and sorting file by key

So I have two language files, english and french. They are in this format: key=translation An example in English would be: ui.title=My Title And in French: ui.title=Mon Titre So I need a ...
1
vote
0answers
51 views

Bash completion function for vim 'scp://' Paths

For easily editing remote files with vim, I currently use a few .vimrc and .bashrc additions to my environment. The bash-scripting side of it "misuses" the available standard _scp bash completion ...
1
vote
1answer
85 views

Awkward awk exit code

I'm writing some awk scripts for data validation. These are intended to be selected and invoked by another proces which needs to see the exit code from the awk script to determine if the content was ...
0
votes
2answers
48 views

sed command to append different text at multiple occurrence of string

I want to use sed command to append text at multiple occurrence of string. For Ex: Hello world types="program" Mario types="Game" Hello world types="program" Mario types="Game" So at first ...
0
votes
4answers
217 views

If condition with ssh command inside

I'm doing a bash script to backup my computer to a local server. I need to compress the archives but I can't find a way to make this if condition work with an ssh command inside: if [ ssh ...
4
votes
3answers
107 views

How to remove space in all sub directories in shell script?

I tried following shell script to remove all spaces with underscores: find $1 -depth -name "* *" -print0 | \ while read -d $'\0' f; do mv -v "$f" "${f// /_}"; done If I have a directory ...
1
vote
2answers
66 views

Escaping a linux command

I'm trying to run a command from a script I wrote that basically replaces a string in file vzctl exec VZID sed -i 's/\/>/address="$IP\/255.255.255.0"\/\>/' "file.xml" The problem is the ...
7
votes
2answers
2k views

How to replace spaces in all file names with underscore in Linux using shell script?

I tried following shell script which should replace spaces from all xml files for xml_file in $(find $1 -name "* .xml" -type f); do echo "removing spaces from XML file:" $xml_file mv "$xml_file" ...
3
votes
2answers
77 views

How do I write a script to automatically optimize all the PNGs in my MediaWiki images directory?

I have MediaWiki 1.25.2 installed on my 64-bit Debian 8.1 VirtualBox machine and I'd like to be able to upload the images/ directory from this installation to my DropBox. Being a cheapskate I'm trying ...
-1
votes
1answer
89 views

sed throwing sed: -e expression #(number), char (number): unknown command: `(letter)'

I wrote a shell script which reads some files and copy all the data from these files to other consolidated file. This happens multiple times and previously copied data will not be copied again. For ...
1
vote
0answers
198 views

bash “no such file or directory” when sh symlink works! [closed]

I use tcsh on a Centos 6.5 64-bit system. I created a file x.sh with two lines: #!/bin/bash echo Yes yes That's it. Then did chmod +x x.sh. # ./x.sh /bin/bash: ./x.sh: No such file or directory ...
1
vote
1answer
38 views

Get the list of packages that are not installed on a Debian system

I am writing a script to print the list of packages which are not installed. #!/bin/bash declare -a LIST_OF_PACKAGES=("php5" "nginx") for i in "${LIST_OF_PACKAGES[@]}" do ...
-1
votes
1answer
21 views

How to select from 2 numbers in a script?

I=1 APPCNT=$(itemCount $APP_LIST ,) while [ $I -le $APPCNT ] ; do APPNO=$(itemGet $APP_LIST $I ) APP_List=6,9 APPNO=6,9 is coming instead of 6 only or 9 only. What can I use instead of ...
0
votes
1answer
64 views

tail file from remote server and nslookup on local

I need a script for resolve hosts. For now I run this script on local machine for i in `tail -F access.log | awk '{print $8}' | awk '{gsub("http://|/.*","")}2' | awk '{gsub("http://|:.*","")}1' | ...
1
vote
1answer
41 views

search and increase the values between the second tilde symbol and the 3rd tilde symbol in each line of a txt file

I was wondering is there any way to search and increase the values between the 2nd tilde symbol and the 3rd tilde symbol in each line of a txt file. Maybe vi can do this? For example, i have a ...
2
votes
2answers
175 views

Save list of echo outputs to .txt

I'm having a lot of trouble at work trying to save a long list of echo outputs as a .txt file on my desktop. I am using Bash in Yosemite 10.10.4. I am still very new to Bash so any help and tips are ...
0
votes
1answer
78 views

How to append extension to files with certain filename format

I have several files generated by a script but I neglected to have the script append a file extension. Each filename contains the substring k120 and no other file in the directory contains that ...
0
votes
2answers
111 views

Get number of files in each directory [duplicate]

I have a directory with a very large number of subdirectories (~800) that were generated programmatically. I want to get a count of the number of files in each of these subdirectories to check for ...
11
votes
4answers
634 views

Fast method of splitting string from textfile?

I have a two text files: string.txt and lengths.txt String.txt: abcdefghijklmnopqrstuvwxyz lengths.txt 5 4 10 7 I want to get the file >Entry_1 abcde >Entry_2 fghi >Entry_3 jklmnopqrs ...
0
votes
4answers
82 views

how to print quote character in awk

I have a file str.txt with the following sample records. 31,2713810299,1,11-Aug-15 19:52:10 32,2713810833,1,11-Aug-15 21:36:18 Now I want to print output with awk as below. cat str.txt|awk -F, ...
-1
votes
3answers
157 views

Why does the builtin `test` fail with 'less than' (<) and 'greater than' (>)?

This code: #!/bin/bash if [ "4" = "a" ]; then echo "equal"; fi if [ "4" > "a" ]; then echo "yes 1"; fi if [ "4" < "a" ]; then echo "yes 2"; fi echo "exit" prints this three lines: yes 1 yes ...
1
vote
2answers
197 views

Odd syntax for ssh and bash to run command

I'm pretty new to shell/bash scripting and I'm writing a script on OSX to automate some rather tedious efforts. I'm trying to run a portion of my script on a remote host using ssh. There's a common ...
1
vote
2answers
160 views

Bash is not sourcing ~/.bash_profile on OSX

I just got this really weird problem. When I start bash, I get these two lines: -bash: fasd: kommandot finns inte -bash: brew: kommandot finns inte "kommandot finns inte" means command does not ...
1
vote
1answer
39 views

Have cron check if the bash script is executing

I have a bash script that users while do along with sleep to constantly monitor the connection state and take measures in case something goes wrong. The only thing that is not guarded is the execution ...
0
votes
1answer
59 views

How can I mount /home in a usb drive and keep the files?

I need to write a script that can mount /home in an USB drive at the boot and keep all the files in the USB drive after ejecting it. At every boot, if there is an USB drive plugged in, the script ...
4
votes
3answers
585 views

Log monitoring using shell script

I would like to monitor a log file for errors and then send an email to administrators. The log file contains data like below 11 Aug 02:30 Service1 restarted 11 Aug 05:35 Service1 restarted 11 Aug ...