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

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0
votes
2answers
8 views

rename a batch of files after reading from a source file

I have a directory full of over a thousand files and the names are bit long (and no pattern found in the naming style). I would like to simplify the filenames. E.g.: ...
1
vote
1answer
12 views

Read Multiple Entries from an Input File

I wrote a program in Fortran that asks me for latitude and longitude and the name of the output file every time I run it. It works great. What I have been meaning to do is run this program for the ...
-2
votes
1answer
34 views

Installation script for OpenERP, creating directories under /var

I would like to know what this code means. I found it on the OpenERP forum. It is supposed to run on Linux CentOS. adduser openerp DIR="/var/run/openerp /var/log/openerp" for NAME in $DIR do if [ ! ...
0
votes
1answer
21 views

What is the term “Usage”?

I am seeing this a lot in the scripts. Is "usage" a command in unix ? I tried googling it but got ambiguous results. Here is an example : ${1?"Usage: $0 ARGUMENT"}
0
votes
1answer
17 views

Connect psftp between Unix and Windows server

I need to transfer files from Unix to Windows server. After creating a folder in the windows server files need to be copied from Unix to Windows. I am using psftp to do this process.So, I am trying to ...
2
votes
3answers
13k views

How to append multiple lines to a file with bash

I am writing a bash script to look for a file if it doesn't exist then create it and append this to it: Host localhost ForwardAgent yes So "line then new line 'tab' then text" I think its a ...
0
votes
1answer
31 views

How to evaluate a variable length in shell script?

I want to write a shell script, in which it will call different command according to the variable length. But I didn't figure it out yet. My unwork script is here: for i in n5 n25 if ${#i} == 2; ...
8
votes
6answers
362 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 ...
2
votes
4answers
93 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 ...
4
votes
6answers
56 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 ...
0
votes
3answers
247 views

compare two files based on a column and print it

I have two big files of 400,000 lines. I want to compare the column 1 of the second file with column 1 of first file recursively. If they match I would like to print the whole line. It is a sorted ...
1
vote
1answer
23 views

How can I use global variable arrays in aliases or functions

I am attempting to simplify repetitive work procedures. In doing so, I am trying to write a .bashrc script which will set global path variables that aliases can refer to. Disclaimer: I'm new to linux ...
-2
votes
0answers
18 views

using mysqlimport on a large amount of csv files in a directory via bash scripting [on hold]

I have a directory with approximately 75 csv files in it that I need to mysqlimport into a MySQL database. The MySQL database does not have the tables created. The files: * The data is all numbers ...
-4
votes
3answers
53 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
1answer
386 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 ...
0
votes
2answers
37 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 ...
1
vote
0answers
34 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 ...
2
votes
4answers
917 views

Split long output into two columns

Is there a simple utility or script to columnate the output from one of my scripts? I have data in some form: A aldkhasdfljhaf B klajsdfhalsdfh C salkjsdjkladdag D lseuiorlhisnflkc E sdjklfhnslkdfhn ...
0
votes
1answer
38 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 ...
0
votes
4answers
538 views

How to get data count between two strings with multiple occurences in the same file

I have the data in my file as START-OF-FIELDS ID NAME DEPT END-OF-FIELDS START-OF-DATA 1|joy|cs 2|sam|ec END-OF-DATA START-OF-FIELDS ID NAME DOB DEPT ADDRESS END-OF-FIELDS START-OF-DATA ...
2
votes
3answers
31 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, ...
-1
votes
1answer
19 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
134 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
50 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 ...
3
votes
0answers
15 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 ...
1
vote
2answers
48 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 ...
12
votes
5answers
4k views

How can I get bash to exit on backtick failure in a similar way to pipefail?

So I like to harden my bash scripts wherever I can (and when not able to delegate to a language like Python/Ruby) to ensure errors do not go uncaught. In that vein I have a strict.sh, which contains ...
1
vote
1answer
12 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
3answers
80 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 ...
5
votes
1answer
1k views

Global /etc/profile setenv or export overwriting user settings in .profile

I need to call a modified version of a program in /home/user_name/bin rather than the (older) version in /opt/program_name/current on a CentOS 5.3 cluster. The program creates a tcsh script using ...
1
vote
1answer
470 views

Command/scripts to check the Reverse DNS Lookup time

I am working on a project in which one master communicates with numbers of slaves. For that it has to make connection with hosts in network. But sometimes it hangs. I think that the reason behind is ...
1
vote
1answer
622 views

Deleting Non-empty Directory with smbclient

How can I remove a non-empty directory with smbclient? I have tried the following: 1) rm Result: NT_STATUS_NO_SUCH_FILE listing [dir_path] 2) recurse;rm Result: No Error but also nothing ...
-2
votes
2answers
166 views

How to get the port number a program is listening on in a shell script? [closed]

I have a program (beam) running, and I need to figure out which TCP / IPv6 port it is listening on. I know netstat will tell me, but I haven't fully been able to parse its output: ...
2
votes
0answers
22 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
111 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 ...
4
votes
2answers
35 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 ...
-1
votes
0answers
47 views

Unique id for combination of Latitude - Longitude

I have a LibreOffice Calc table containing one column with latitude and one with longitude. What I want to do is for every unique combination of latitude and longitude a unique number to be assigned ...
2
votes
1answer
35 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 ...
2
votes
2answers
76 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 ...
1
vote
1answer
25 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
vote
1answer
45 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 ...
2
votes
0answers
29 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, ...
1
vote
0answers
23 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 ...
6
votes
7answers
202 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?
0
votes
1answer
1k views

Why does scp say “No such file”?

I have a bash script that uses scp to copy a file from my machine to another. The script keeps on exiting after I enter the SSH password with the error: <filename>: No such file or directory ...
3
votes
3answers
51 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 ...
3
votes
2answers
37 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 ...
8
votes
3answers
383 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
159 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)
1
vote
3answers
3k views

Print given number in reverse order

clear echo "Enter a number" read n sd=0 rev=0 while [ $n -gt 0 ] do sd=$(( $n % 10 )) rev=$(( $rev *\ 10 + $sd )) n=$(( $n / 10 )) done echo "Reverse number of entered digit is $rev" ...