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

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4answers
183 views

How to delete the files in one folder which are more than 60 days old in UNIX?

I know how to delete the files which are more than 60 days old by modification time, but I want to delete files based on a timestamp in the file name. For example, I have the below files for each day ...
1
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5answers
98 views

find the max value of column 1 and print respective record from column 2 from file

How to find the max value from the column 1 and echo the respective path location from a file which contains n number of records. $ cat version.log 112030 /opt/oracle/app/oracle/product/11.2.0 ...
3
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1answer
46 views

How to find out the biggest number in many documents that contains different numbers

For example, there are some temperature data at those folders in different time. temps.txt contains the temperature number. So how can I use bash script to find out the maximum temperature? (the ...
1
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2answers
52 views

How to get 2 different outcomes from 1 file in unix?

So I'm trying to make a dungeon and I want to have 2 different responses when I enter the one room but I thats as far as I can get. How do I get 2 different outcomes from 1 file? So when you open a ...
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1answer
58 views

bash script programming question

Why the stomach of cat has ": No such file or directory" ? Help me please! #! /bin/bash if [ $# != 1 ] ; then echo wrong arg,please input one arg exit 1; fi if grep '^[[:digit:]]*$' ...
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1answer
17 views

Tool to add hierarchical structure to output, similar to tree

Is there a tool that is similar to tree which could be used in conjunction with echo? I want to easily prepend hierarchical structure to output. I know I could write it, but if a solution ("do one ...
1
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3answers
63 views

How to test for unknown commands in shell script?

I would like to know, if there is a way to go through a shell script and getting a warning for every command, that is unknown. I know bash -n for syntax checking, but it doesn't tell me, if there are ...
0
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1answer
23 views

Confusion about basic bashscript loop - until/done [duplicate]

I have a bash script I'm working on to help with an installer. why doesn't this work? function fn_myFunc(){ local MYVAR=0 until ["$MYVAR" -ne 0]; do whiptail --yesno ...
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3answers
282 views

Press any key to pause shell script, press again to resume

I've written a shell script for testing an API that copies files and echoes its progress after each one. There is a two second sleep between each copy, so I would like to add the ability to press ...
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0answers
36 views

making a delete script and a restore script

I'm looking to create two scripts; one to "delete" a script, and one to "restore" I need "del " where this will move the file located at to the dustbin directory in a way that will allow it to be ...
-1
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1answer
28 views

how to replace a specific pattern from all files [duplicate]

suppose I want to replace abc with xyz in all files in a directory. How do I write a script for this ?
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2answers
83 views

Update process name in shell, is it possible?

In C/C++ it is in general possible to do strcpy(argv[0], "new process name"). It's a hack used in malicous software to hide real process name. Is such operation possible via shell? What I want to do ...
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0answers
35 views

trash and restore script - issue restoring

#!/bin/bash echo "Are you sure you want to move this file to the Recycle Bin?" "(Yes/No)" read ans case "$ans" in Yes) echo "$(readlink -f $1)" >> "$HOME/TrashLog" && mv "$1" ...
0
votes
1answer
47 views

check status process output

I wanted to understand how to create a script sh that allows me to see if an additional script functions correctly. For now this is the script that I created. if /run.sh status echo "$SERVICEXE ...
1
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1answer
28 views

'hhighlighter' wrapper script saying command not found

I have gotten the wrapper script 'hhighlighter' from https://github.com/paoloantinori/hhighlighter which colors anything you want in stdout. I followed the instructions about installing ack-grep, ...
2
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1answer
31 views

Command Line Macros in Comments using SLURM

In my opinion, comments are comments are comments. They should NEVER change program state. Sadly, the people over at SLURM disagree. SLURM requires the following syntax (or something similar) to ...
0
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3answers
74 views

How to print only certain characters?

I have to translate the permissions of a file this way: r ► c w ► s x ► e Then, I must extract the group of characters which are related to owner group. Last step is to print that group of ...
0
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3answers
59 views

Find the parent of a process

I am trying to write a script to help with computer security. I am trying to look for open ports, find the PID, and find what called it. I have it working, where my output looks something like this: ...
1
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3answers
187 views

Is there a difference between “a=b” & “a=$b”?

I came across two Unix scripts in my textbook. In one of them they implemented a=$b (in the form of max=$a) and in the other a=b (in the form of number=num). Question Are these the same thing or is ...
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1answer
58 views

Editing lines in a file using a bash script?

I am creating a bash script that installed VSFTPD / FTP. After the installation some configuration is required in the "/etc/vsftpd/vsftpd.conf" file. This includes making sure the following lines are ...
6
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7answers
496 views

Command line tool to “cat” pairwise expansion of all rows in a file

Suppose I have a file (call it sample.txt) that looks like this: Row1,10 Row2,20 Row3,30 Row4,40 I want to be able to work on a stream from this file that is essentially the pairwise combination of ...
1
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2answers
102 views

Sort files according to their extensions

I have made a script that will sort files according to their extension and place them in the proper folder. For example, place abc.jpg in the directory jpg. #!/bin/bash #this script sorts files ...
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2answers
48 views

How do run MYSQL scripts from a shell script with bash variables?

Im making a script where I connect to a database, look for a value and then if that value returned something then I will do something else. ip=$("variable is defined here") Then I connect to the ...
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0answers
17 views

Bypassing the security message in Debian 7 when creating a bash script? [duplicate]

I've created a bash script which involves the installation / update of wget. As a result there is also a message from Debian showing the following: wget (1.13.4-3+deb7u2) stable-security; ...
1
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1answer
88 views

Ubuntu runuser command?

I am creating a bash script that requires to run commands as a specific user. As a result I am using the command: runuser I have tested this script and it works perfectly in Ubuntu Server 14.10. ...
0
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2answers
66 views

Percent signs and environment variable in a shell script

While troubleshooting an issue, I came across these entries given below in one of the shell scripts used by our application. This was written by someone who no longer works in the company and I am ...
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5answers
266 views

Calling multiple bash scripts and running them in parallel, not in sequence

Suppose that I have three (or more) bash scripts: script1.sh, script2.sh, and script3.sh. I would like to call all three of these scripts and run them in parallel. One way to do this is to just ...
1
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2answers
52 views

Why double ampersand chained conditions runs in background together the last one?

I have some conditions for some background job to run: condition-command && condition-command && background-job & The problem is: I want the conditions to block until the job ...
0
votes
3answers
73 views

Group by and sum in shell script without awk

I have a file like: $ cat input.csv 201,100 201,300 300,100 300,500 100,400 I want to add the values in column 2 which has same value in column 1. Expected output is as follows: $ cat output.csv ...
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2answers
39 views

disk space by individual user

I have around 50 user folder under etc/main/ folder. Now i want to get 10 large space user folder detail. Note: I don't want sub-folder of each user..I am using Ksh script. Example: /etc/main$ ...
0
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0answers
10 views

Running a script with elevated privileges [duplicate]

I need to find a way to run a script with elevated privileges but without compromising security. One suggested that i should use setuid but i don't think that is an option since it can cause serious ...
2
votes
2answers
152 views

Negative arguments to head / tail

Variants of this question have certainly been asked several times in different places, but I am trying to remove the last M lines from a file without luck. The second most voted answer in this ...
0
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1answer
70 views

sh script cannot run process

I have fairly simple sh script that checks if process is running, if not then start it. My problem is that sh script cant start the program for some reason... Here's my script: #!/bin/sh if ps x ...
0
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1answer
37 views

How to Trim below highlighted lines from Shell output

How to Trim below highlighted lines from Shell output. Source shell program is below the output. $ ./checkhome.sh The Oracle base remains unchanged with value /opt/oracle Connecting ...
2
votes
3answers
256 views

Bash File existence test is always true

I have the following lines of bash script to test whether a file exists: MYAPPPATH=$(find $APPDIR -iname myapp* -print) if [ -e $MYAPPPATH ] then echo "File exists" fi However when file ...
0
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1answer
21 views

How to script with systemd-cgtop?

The manpage for systemd-cgtop says that if there is no attached tty it will do one iteration and then print it out, saying that this would be useful in scripts. However when I try to do this from a ...
3
votes
1answer
58 views

Split input file into X parts of size total lines / X

Currently, my bash script splits by number of lines. However, I'd like to split a file into X pieces, each of those having total lines equal to the file length divided by X. The script is run as ...
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0answers
47 views

Cron can't access my home directory when I'm logged out

I have quite a strange problem using cron. I distilled it thus far: I created following simple bash script in /home/user1/cron_dir/cron.sh: #!/bin/bash echo "Success" As user1 I created following ...
2
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2answers
82 views

Inputting user input automatically through bash script? [duplicate]

I am creating a bash script which creates a user and sets a password. When the command "passwd user" is run it requires the user to enter a password and stops my script. Is there any way to fulfill ...
1
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1answer
86 views

Sh Script using ftp to put a list of files

So my Script looks something like this: #... files="$(find $line/processed/* 2>/dev/null)" #2>/dev/null used for error output suppression if [[ ! -z "$files" ]] then ...
1
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1answer
188 views

How to get owner and full path of 50 large size file across all users?

Below command list top 50 files regardless of subfolders. $ls -lR /root/home | sort +4 -5nr | head -50 Current Result: -rw-r--r-- 1 john dpst 192954384 Nov 7 07:36 filenxx1.gz ...
1
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1answer
32 views

Is there a way using a bash script to get the location of changes made in last git commit?

I need to check the location of the files, which were changed in the last commit. Because I will have to do this on Jenkins, this should be done using a bash script. This is the output of git ...
1
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3answers
95 views

Generate networking configuration files using sed and bash

I am a bit rusty on my scripting abilities and am trying to find a good starting point for creating a script that creates files (generating new file names) and edits the IP address in the file by ...
0
votes
2answers
39 views

how to insert backslash at the front of # symbol?

In bash programming, given a variable, say varA, that store a string containing # symbol. Let's assume varA contain this value: ASD# 1, I need to append a backslash \ at the front of #, so the output ...
0
votes
1answer
66 views

How to ssh and execute a remote script within a local shell script?

I have a shell script which will kick off a series of jobs on a remote server. I can ssh into this server (but it does require a password!) and run the scripts manually, but there are certain steps ...
1
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2answers
54 views

syntax error in conditional expression

I am writing a script where I am using the combination of logical 'OR' and logical 'AND' statement. This is the script: #!/bin/bash echo "Enter the value of a" read $a echo "Enter the value of b" ...
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2answers
79 views

syntax error near unexpected token `<'

I am writing a script to read the output of a command to variable a and b. This is the script #!/bin/bash read a b < <(awk '/Application Server/ && !seen[$7]++{printf "%s ", $7}' ...
2
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1answer
51 views

What is the most portable syntax for `if` statements?

(NOTE: There is a very similar question, asked yesterday oddly enough, but it doesn't cover the main syntaxes I'm concerned with. If I were to update the other question to include them it might ...
2
votes
3answers
85 views

How to open terminal, split to 9 terminals and switch between them using one script?

I would like to open a terminal, split it to lets say 9 parts (3x3) and execute some bash script. But for each terminal part different script. Can this be done using perl, python or even bash? How ...
0
votes
2answers
55 views

How to list files and directories of a mount point

Given a mountpoint such as /dev/sda1 how can I list the contents of this file system using shell script. My objective is to delete the oldest file in this drive.