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

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1
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0answers
79 views

How to properly start and stop shell script in linux, busybox?

I am trying to write a small shell script that would send some commands to my tv set from my set top box that has busybox on it. The problem is that it generates huge amount of zombie processes, and ...
0
votes
2answers
87 views

How to kill a process in shell script which is running through cron?

I have a shell script which runs in cronjob. This shell script has to kill a process which is running and start the new process again. When I run the script manually it works perfectly fine, but when ...
-4
votes
3answers
97 views

Birthday reminder

write a bash shell script to get the alerts of friend's birthday Suppose Birthday Date Friend's name 08-02-2014 : Prashant 08-15-2014 : prabhat 09 -16 -2014 ...
2
votes
4answers
112 views

Change to the last modified subdirectory of the current directory

I have an application which generates a couple of files in different directories at a regular interval and I need to check the latest files generated, i.e. the file which is generated in the most ...
0
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1answer
80 views

Writing a Bash script to run and end at specific times

I'd like to create a script that will do the following. Start at a given time during the day and end at another given time. So for example, I have a program I'd like to test, so my script would be ...
-1
votes
1answer
21 views

A command showing if I have the right to perform writing?

I'm searching for a command which only says if the current user has r-rights (read) on the file passed as a parameter. This command could be something like haveIRights -x <file> and it has to ...
8
votes
1answer
168 views

How to append multiple lines to a file with bash, with “--” in front of string

Question very similar to How to append multiple lines to a file with bash but I want to start the file with --, and also append to the file, if possible. printf ...
2
votes
3answers
77 views

moving a (file | directory) while avoiding filename collisions

I have a bash script that moves files from a number of different locations to a folder named completed. I want to avoid overwriting previous files, so in the case when the name of a file (for ...
2
votes
3answers
87 views

waiting for network in a bash script

I'm running a script that relies on network being up and a network share be mounted. The script runs on login (which happens automatically after boot). The problem is that by the time the script runs, ...
3
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0answers
18 views

Get notified from avahi

After looking for a zero-conf browser valid implementation I realised that inside my linux machine (ubuntu) I already have avahi and typing: avahi-browse -alr I get a complete list of all devices ...
8
votes
6answers
706 views

How can I test if a variable is empty or contains only spaces?

The following bash syntax verifies if param isn't empty: [[ ! -z $param ]] For example: param="" [[ ! -z $param ]] && echo "I am not zero" No output and its fine. But when param ...
0
votes
2answers
163 views

Unix Shell Scripting output to an Excel File

I have a Shell script with Multiple SQL statements like this: select Count(*) from Emp where date= current_date-1; After executing the Shell script i need a MS excel file to be create with Column ...
2
votes
3answers
118 views

Count files in a directory by extension

For the purpose of testing, I'd like count how many images files are inside a directory, separating each image file type by file extension (jpg="yes". This because later it will be useful for another ...
1
vote
1answer
41 views

Make some fields required in dialog

The script below creates a dialog box. The user can press Enter at any time, and then the script continues. I need to block the Enter key to ensure that the user fills all the fields. How can I do ...
2
votes
0answers
199 views

Running shell script inside with vagrant provision

I have setup a vagrant box using precise64 (ubuntu 14.04) and installed packages needed for octopress. I can ssh into the vagrant box and generate posts and run preview for my octopress site. Now I ...
4
votes
1answer
124 views

Proper way to distribute shell scripts

What is the most proper way to distribute shell scripts, if behaviours of shells can be modified by set and thus are unpredictable? For example, rm *.txt wouldn't be executed as expected on the ...
2
votes
1answer
56 views

Arrow key/Enter menu

I need help finding out how to possibly create a menu in a shell script that will display 3 options that a user will use the arrows keys to move the highlight cursor and press enter to select one. If ...
1
vote
1answer
39 views

bash script not being run by cron [duplicate]

I have a very simple bash script that runs flawlessly when I do ./removeOldBackup.sh or sh /home/myusername/backup/removeOldBackup.sh but when I add it to crontab like * * * * * sh ...
1
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0answers
31 views

Trap not trapping SIGTSTP

I have a script that keeps displaying the login prompt: #!/bin/bash trap '' 2 20 while true; do login done This is part of a bigger project so please don't tell me to just use the system login ...
4
votes
2answers
38 views

How to sort a collection of lines from different files?

I want to sort second line in each file by second column, and also print name of the corresponding file. I am doing it like this - rm tmp; for filename in file*; do num=`head -2 $filename | tail ...
2
votes
2answers
97 views

How to clear the input in Bash

I have a bash script that is reading quite a bit of data /dev/random. I need the user to type randomly to seed the random daemon. However once the script completes everything typed will get dumped to ...
2
votes
1answer
62 views

Memory buffer in a bash script

I have recently finished a script that will ask for a hostname and automatically take the argument of the function and ssh into one of my work servers. Here is a copy of my script: #!/bin/bash echo ...
6
votes
7answers
245 views

Count total number of lines before/after a pattern match

I am having a long list of IP addresses, which are not in sequence. I need to find how many IP addresses are there before/after a particular IP address. How can I achieve this?
2
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0answers
43 views

Shell scripts for the database logs

The actual log file will be like this $ cat file1.log time=2014-07-23 23:56:28 GMT, user=[unknown], db=[unknown], host= pid=28254 LOG: time=2014-07-23 23:56:28 GMT, user=portalman, db=ss, ...
3
votes
3answers
61 views

How to read a text file line by line which is not constant in shell scripting

I need to read a text file line by line and the lines are not constant it may vary.For example $ cat file1.txt syntax error at or near "?" at character 1 syntax error at or near "[" at character 1 ...
8
votes
3answers
562 views

Creating a Bash script that will execute a program and if it exits without crashing, will run it again

I'd like to know the easiest way of creating a bash script that will run an app in MacOSX (it's a UNIX based system so I assumed this was the right place). wait for the program to exit. If the exit ...
6
votes
2answers
171 views

Is there a way to convert a zip to a tar without extracting it to the filesystem?

Is there a way to convert a zip archive to a tar archive without extracting to a temporary directory first? (and without writing my own implementation of tar or unzip)
4
votes
6answers
105 views

reading a list of lines from a file writing output to a utility

I have a file with a list of lines I want to read from another file. I want to output those lines to a utility (grep) that lets me read the entire line and pull information from it. The file with the ...
3
votes
2answers
82 views

fdupes - delete files after comparing two directories

I'm currently trying to solve an issue using fdupes. I'd like to compare two folders with each other, and afterwards delete all duplicate files within one of these directories. Example: Files are ...
2
votes
1answer
50 views

How to set parameter zero ($0) while executing a script?

I can manipulate positional parameters using shift or set -- while a script is interpreted. How can I change $0?
1
vote
2answers
204 views

How to iterate through multiple file extension without caring about case sensitivity?

I've seen various topics on how to iterate through multiple file extensions but in most case, the list is defined. example: for file in ${arg}/**/*.{txt,h,py} do .... done As can be seen, ...
5
votes
3answers
210 views

How to iterate through a list of files with spaces that is sorted (case insensitive)?

I am doing this in OSX which uses bash but obviously, not all bash conventions are used so hopefully your suggestion is available to me :) I have the following files fun bar1.txt Foo bar2.tXT ...
-4
votes
2answers
130 views

“bash: [: : integer expression expected” [closed]

I want this function to return one random word if there aren't any command-line arguments. I am modifying linuxconfig.org's random-word generator to run even when #$ -ne 1. function random-word { ...
3
votes
1answer
69 views

How do I use sudo to run multiple commands as another user within a portion of a script?

I'm trying to run the following: if [! -f .owner ]; then creator=$(whoami) sudo -u appuser ksh echo "$creator" >> .owner mkdir test1 test2 test3 exit fi However, the ...
2
votes
1answer
58 views

Fetching Remote Windows System Information From Linux Server

I need a script/command that would fetch Windows System Information (Host Name,User Name, Domain, OS Info, Hardware Info, Memory Info, processor Info, etc) by running it on a Linux Server (RHEL 6.5 ...
6
votes
3answers
413 views

How you stop 'wget' after it gets a 404?

If you use brace expansion with wget, you can fetch sequentially-numbered images with ease: $ wget 'http://www.iqandreas.com/sample-images/100-100-color/'{90..110}'.jpg' It fetches the first 10 ...
3
votes
1answer
40 views

Triggering Bash Before Killed [closed]

I just made some kind of service code. Check this out: do_start() { while true do if [[ $(pgrep -fl loopsvn.sh | wc -l) -gt 2 ]]; then echo "Already use by another ...
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votes
1answer
28 views

add groups from external file

I want to write a script which add groups to the system, specified in groups.txt file. content of groups.txt : group01 : computer group02 : electronics group03 : IT . ...
12
votes
4answers
642 views

Recursively create directories for all letters

I want to create a directory in such a way that I need to label the directories from a to z. Inside each of these directories, I need to create sub-directories so that they are labelled as aa, ab etc. ...
2
votes
2answers
64 views

Call the script after disconnecting from server

I have a script I made for work that will call a function that takes an argument. I use the arguments to ssh into our servers. My question is: Is there a way to call the method so that if/when I get ...
6
votes
2answers
99 views

Passing arguments from a file to a bash script

I' ve got this situation: ./ ./myscript.sh ./arguments.txt ./test.sh Inside myscript.sh, i have to run the file test.sh, passing to it the arguments contained inside arguments.txt. myscript.sh is: ...
3
votes
2answers
85 views

transfer a file to remote dir only if doesn't exist without replacing

I'm using CentOS linux. In one line cmd, that returns 0 if success, non-0 if failure, I need: Transfer a file to a remote server. Don't transfer the file if filename exists in remote server ...
4
votes
6answers
196 views

Finding the number of time a particular number in a file where range also specified

I have a file with numbers separated by ,(comma). In between it also contains a number range like 300-400. Say for example I have a text file, namely testme.txt which looks like, ...
2
votes
1answer
70 views

Asteriks in filename as wildcard not working [closed]

So I have a folder with many files like 20140720.457812.tmp and I try to count how many lines they have, I tried this: #!/bin/bash lines=`more /folder/20140720*.tmp|wc -l` but I get this error: ...
4
votes
3answers
129 views

Frequency of words in non-English language text: how can I merge singular and plural forms etc.?

I'm sorting French language words in some text files according to frequency with a focus on insight rather than statistical significance. The challenge is about preserving accented characters and ...
1
vote
1answer
88 views

Formatting an external HDD with Bash script

At my workplace we have an external HDD connected to a NAS device (Synology). There is a backup tasks which runs weekly and fills the external HDD after a while. Unfortunately the Linux-based OS of ...
0
votes
0answers
112 views

How to find the cpu and memory usage of a single process in linux

This question is similar to this SO. I wanted to find the CPU and memory utilization for a single process so I decided to use the top -p <$PID> as mentioned in the question. Here is my script. ...
2
votes
1answer
33 views

What do I need in my script to be able to change ownership of a directory structure that belongs to root to the current user running the bash script?

My bash script has the following section: su root -c chown -R smithb:other /export/home/smithb/workspace/rootownsit/ exit The directory rootownsit and its two sub directories were created and is ...
5
votes
1answer
130 views

How to continue a script after it reboots the machine?

I'm writing a shell script in bash. At some point in the script, it detects that the machine needs to be rebooted before continuing. It issues: sudo reboot When the machine comes back up, there ...
0
votes
0answers
25 views

A script to identify whether a file descriptor has gone bad

Problem : I have a server program running which connects to a remote program using TCP sockets. There many of them (say 20). My problem is one of the socket descriptor has gone bad and has recieved ...