Programming :: Bash Scripting - Taking User Input And Adding It To A Particular Area Of A File?
Jan 12, 2010
in bash scripting...say I want to take the input from a user via a question...I would do this:
Quote:
#!/bin/bash
echo "How large do you want this partition to be in GB (enter only the number)?" read PART_SIZE echo "You want your partition to be $PART_SIZE GB" But I don't want to echo it back to the screen, I want to add it to the content of /etc/fstab. I have been mucking around with sed to find the tmpfs partition in /etc/fstab and add the partition size attribute (this is to use the onboard RAM as a volatile partition)...but am not having any luck...
The portion of /etc/fstab that uses /dev/shm for the tmpfs partition is:
tmpfs /dev/shm tmpfs defaults 0 0
So, if a user says "24" GB to the answer (from above), how do I get it to automatically add that value to the tmpfs partition line in /etc/fstab? So it would look like:
tmpfs /dev/shm tmpfs size=24g,defaults 0 0
I understand that I would also have to come up with a way to put "size=XXg", which I could do with a copied over generic file before this action...then the script would have to find "XX" and replace it with the user's figure...
I have a system setup script for my Slackware installations that pulls all packages and source files from another machine and sets everything up to be identical between machines. The script works as expected but make it entirely unattended. How do I make the bash script deal with automatically selecting "Yes" for, for example "Install x(Yes/No): " when prompted by a make file?
I'm creating a bash script to do some tasks for me. I would like the script to be run at a set time of everyday. My first question is if it is possible that if one of the commands in the script requires sudo, is there a way to get around it with out making sudo not require a password. Such as, is there a way to include the password in the script? If that is the case, I can always just set the file as read only by sudo. I've been looking for a way to do this, with no success. if I have a command that wants input, how do I give it to the program. For example, if I want to make a zip file that is encrypted, the command would go as:
Code:
zip -r example * -e
now how would I get the script to insert my wanted password.
the problem i have is that when i enter my username, the output (my real name) does not display in the output.txt. instead it displays in putty. so when i run my script in putty it shows the message to enter username and after i enter my username my real name appears below it. i want it to show in the output.txt
I have a file called list.txt with on word on each line that changes in length. I'd like to make a menu, each line being its own choice. I pieced together most of it the only thing missing is a failsafe for typing a number out of range
I've written a bash script that allows a user to input a directory location to find out the size of the directory. However, if the user inputs a directory and finds its size then inputs another directory then wants to quit, the script asks the user numerous times if he wants to quit!! The script won't exit until the number of times the user looks at a directory is reached! What gives?
I've been using python/bash to help myself automate things for a long time, however I am curious. One reason I use python more is because I don't quite know how to work with user input in Bash, such as getting it to ask for input and wait, and then placing that user input into a command.
Here's an example of a script I use from time to time for converting OGG video files into AVI.
How could I write this same script in Bash? Keep in mind I am mostly self taught, so I am by no means an expert programmer.
I have a script im having some problems with, what I need is to have the system generate a random password for me and use that password when creating new users to it.
System is Debian Lenny and script is in bash.
The program is znc. I have made it so that it will generate the random password on the shell but the problem is to use it in the bnc software.
To make a password there the command is znc --makepass and look like this:
My question is now if it would be possible to put in the script so it would "answer" when it need those passwords ? the random password that is generated is in a variable called $setpass and is NOT crypted.
Or is there any other software that would be able to generate that md5 string for me ?
At my wit's end I can't find anything that I understand well enough to use. This is for a Unix class, we are working with shell scripting. File1 has 5 in it and File2 has 100 in it.The teacher wants us to read the values then do the math. This is what I have so far:#!/bin/bashvar1='cat File1'var2='cat File2'var3=`echo "scale=4; $var1 / $var2" | bc`echo The final result is: $var3
Is there a way to process individual characters one-by-one from a text file in Bash, or is that hoping for a little too much from this lovable old clunker?
How do you catch user input while the script is running? Or, how would you make two scripts run at the same time, but use input from one script to the other? The program I'm trying to make, echos text on the screen continuously, but while thats happening, I want the user to be able to input something, so the program can detect the input and display something else. So I thought maybe I could make two scripts run to do each task.
I'm trying to call a specific variable based on a user selection. For example:
Code: Select a file:
[1] foo.tar [2] bar.tar
Enter a selection: I have already coded each possible selection to have its own variable. If the user selects 2 I need to select $SELECTED_TAR2, or if they select 1 I need to select $SELECTED_TAR1 and then do something like this behind the scenes:
Here's a challenge I've been struggling for months with:
I have a bash script that reads URL addresses of our internal server and then executes some test commands on them. Something like this:
Code: read -p "Enter URL: " url sh execute-what-ever-to $url
After copy-pasting the URL the user taps the enter key and the script proceeds, but here comes the tricky part: I want this to work without the need to press the enter key after copy-pasting the URL.
"read -n" does not work in this case, as the URLs vary greatly in length. However, the URLs always end to the same string. They could be like "http://url1/END", "http://url2/END" and so on. So this ending string "END" could be theoretically used to recognize that the whole URL has been pasted.
I'm writing a script to execute bash commands in the PHP CLI. I would like to suppress errors from bash and write my own error message if an error occurs. So far I have this (assuming log.txt doesn't exist!):
Code:
tac log.txt 2>/dev/null
Which works as expected, tac kicks up an error but the error is suppressed, but when I use this:
Code:
tac < log.txt 2>/dev/null
I get:
Code:
bash: log.txt: No such file or directory
The tac error is suppressed but bash still gives me a dirty error.
I have a script which checks on my jobs that run on some cluster.The script, "script.sh", takes as an input the job-id for the job to be checked. Sometimes I have 100s of jobs and I want to check them all (for successful completion.) I could put these job-ids into a text file, "job-id.txt", each id in its own line.For each job-id, the script would ask me few questions (with a yes or no answers) to see if I want to do some other checks for each job-id.I want to know how may I direct my job-ids from this text file into the script one job-id at a time.
Write a program that requires the user to input the name of a file as an argument. If the user fails to include one argument it should make use of a thread that handles a signal. The signal handler should tells the user Incorrect number of arguments and then calls the terminate signal on the process.
If the numbers of arguments are correct then the program should allocate memory space to the file (5MB) and create a child process that requests the user for a character that it should send to the parent. The child should keep request for data until the user keys in the character O. During each request it should pause for 10 seconds, send the character to the parent and then requesting again for another character.
The parent should get the character from the child. Do not make the parent wait for the child to finish requesting for data. Make use of pipes to facilitate communication between the parent and the child. A second child should be created to read and display data from the file. Make use of any appropriate Inter Process Communication technique to ensure that the second child and the parent do not access the file simultaneously (Mutual exclusion).
Now in my bash script, I want to get the output /home/user instead of $HOME once read. So far, I have managed to get the $HOME variable but I can't get it to echo the variable. All I get is the output $HOME.
The two shell scripts (t1prog and t2prog) are given below they are working fine. The input for the first program is 't1.det' and for second program is 't1.rnaml'. These two input files are in 'dir1' folder. I am executing the shell like 'sh t1prog > t1out' and 'sh t2prog > t2out' from this directory only. Then I am executing a java program 'java RNA'; for this, t1out and t2out are input files used in the program and I am getting the final output on screen.
The input files 't1.det' and 't1.rnaml' are in different folders with same name and with different values. Each folder specifies one gene sequence input files.
In mfold directory there are 5 directors and each directory contains these input files as shown below cd mfold dir1 dir2 dir3 dir4 dir5 cd dir1 t1.det t1.rnaml
[Code].....
for inputs in different directories and executing these and redirecting the final ouput after executing 'java RNA' statement to a file is needed.
I need to find a way to download the attachment from a daily report e-mail to me. The kicker is it will need to be down with a cron tabbed bash script.For example, which linux based CLI client is best suited to be scripted?
I'm trying to put together a script that will quickly run through an archive directory of log files that are named by day of the month 01.gz, 02.gz, 03.gz.... 31.gz. The script uses gunzip -c | grep | wc to count up the total number of hourly occurrences of a filename and outputs the results to stdout.
The only snag I have left is the octal limit when it gets to 08 and 09. I've seen examples using perl and awk, but this script uses a number of nested for loops and if statements that I don't want to have to rewrite in a different syntax. I found that I can use num=10#08 to set that variable to a base 10 instead of a base 8, but then I lose the leading 0 again when it passes the number to the next filename variable.
You are probably using systemd (check it with ps --pid 1) and therefore /etc/init.d isn't considered for autostart. Here can you find some information about systemd and autostart [1]. As far as I know systemd isn't intended to start applications with systemd. I recommend you to use the autostart feature of your window manager or desktop environment or at least the .xinitrc.
looking to write a dependency map tree that creates a tree structure of object names . This tree will be written to a file and read back to create the tree structure of files . how to write this using bash ?
I've been using Ubuntu for about 6 months now, but haven't had a need to start scripting until just recently. I know programming basics, but that's about it.Anyway, I have a program that I would normally run in this manner (note that I didn't create a permanent alias because I've been moving the program around a lot):alias dx='python /path/to/dxProgram.py' dx A_input.dx B_input.dxSo, you see, program dx takes two input files, and 'A' must come before 'B'. I have a folder full of these types of files that I'd like to loop through with this program. They're named as follows:
I need to write a bash script that will allow me to manage my "virtual network" (in reality just a bunch of directories and files). I need to obtain something like : I have my own command 'connect'. We can use it in two different modes: user and admin. If I type 'connect adashiu virtual_machine_name, computer will ask about password, if password is correct he will change a prompt to :
adashiu_at_virtual_machine_name >
after that user can start to use commands reserved only for user mode. Analogically with admin mode: prompt 'admin >' and administrator can only use bunch of commands reserved for him. changing prompt and separated commands for user and admin ?
I've got a situation. I'm having GNU bash version 3.00.16(1) on Solaris 10. I need to declare an array say arr1 which will be populated by an output of a command.
declare -a arr1 arr1=( $(/some/command) )
Supposing it will eventually (after executing the command) have element values as -
arr1[0]=1234 arr1[1]=5678 arr1[2]=7890
Now, I need to declare another set of arrays, one for each of the element values above - e.g.
declare -a arr1_1234 declare -a arr1_5678 declare -a arr1_7890
And I also need to populate elements of each of above 3 arrays with output of another command in a loop. So, these arrays will hold values something like -
I'm able to declare and populate arr1[*]. My question is how do I declare, populate and print the subsequent arrays and their elements?I am feeling rather thick to get this working.
