Programming :: Looping Using While Read Line And A Variable Instead Of A File?
Sep 24, 2010
I created the following.
x="top
middle
bottom"
I would like to make the following work.
while read line
do
echo $line
done
instead of importing a file I would like to use the variable $x I tried using pipes, but with no luck. My goal is to read one line at a time, but not have to export my data to another file, I would like to keep it all within one script.
I'm trying to read content of file to variable and use this variable in for loop. The problem is, when I have c++ comment style in file - /*. Spaces in line are also interpreted as separated lines.
For example:
Code:
Changing $files to "$files" eliminate these problems but causes that whole content of variable is treated as one string (one execution of loop).
I have two txt files containing x and y coordinates: xcoord.txt & ycoord.txt. I need to open them; read them line by line to get each coordinate; then each time I need to update Xs and Ys parameters inside another file called "dc.in" with the grabbed values.
Finally each time I need to run two exe files ( dc_2002 and st_vac) and produce corresponding output for each Xs and Ys ( dc.in is an input file for this exe files)
I have written the following code but it does not work:
bash 3.1.17(2) I'm trying do write a shell script which must operate on each line of an ASCII text file. So, all the code must be inside a loop, and inside the loop, the first thing should be to read the next line from the file. I have the bash read command. But it reads from stdin. Any way to make read from a file?
I need a qtimer to trigger reading of a file line by line, I have the code sort of running with the timer trigger but qtimer will just read the first line over and over as it is now.
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: $var3
when I ran both ldapsearch commands invidually, they work fine. But when I ran script, I got first file correctly but not the second one. It looks like its not reading the first file correctly and not setting the variable ($userdn) value correctly in the second ldapseach command. I want read first file first line and run the second ldapsearch and continues, then read the second line..and so on.
have been playing around with a script for a few hours and now I need to be able to output the lines in a text file one by one to be used later in the script.What it gonna do is to read a log file and grep the usernames, then write them to a file, and then run one script for each user, to search for more information about them in the log.But I don't know how to output a single line from a file, and google does not return any solution.
i am trying to read in a file 1 line at a time and for some reason it stops printing out at about line 62,000.
i am doing this: Code: while(fgets(c0, 1085, fstream0) != NULL)
but after about 62,0000 lines it stops printing. no seg-fault, no core dump. it just stops printing to the terminal then returns me to the command line after a couple of minutes. as a hack i am doing split -l 50000 on the input and calling my program 5 times.is there some limitation on fgets that i am not understanding ?
I'm writing a program which now accepts user input:
Code: echo "Enter a date in the format YYYY MM DD hh mm ss."
read gregyr gregmo gregdy greghr gregmn gregsc This lets the user input a date and time, such as 2011 06 21 15 12 45, and have each number assigned to their corresponding variable. Later in the program, these variables are put into an equation, and then the terminal spits out the answer. Now I have to have the program read all of the lines from a text file, which is in this format, assign the variables.
I ran into it while google Segmentation Fault. I'm writing a simple C program that reads a file that counts each line and numbers it then writes to a file called sdout. I copyed my program mostly from the text book but im still having problems. Heres my code:
I am trying to write a script which can read the names of all folders within a given folder into separate variables. In effect, if a folder contains a folder "Folder1", "Folder2", "Folder3", the script would read those names into variables such as:
I just learn perl script.May i know how to simplify the code below especially in the red color part? i saw some examples in internet, they use "next" command.
What's the best way to read a value from a configuration file into a script?I'm trying to get the command_file vaule from nagios.cfg into a script, this works but what's the best way to do it?
Code:
command_file=$(perl -F= -lane 'print $F[1] if /^[[:space:]]*command_file[[:space:]]*=/' /etc/nagios/nagios.cfg)
I googled and tried to find an easy step by step-by-step guide on how to use a bash script read a variable from a file. This is the way I did it (but it does not really work so something is wrong, but what?) (testfil2 contains one line that readsidnumber=1578
I want to get the last term of an unknown-sized text line, by usig the awk command. Is there any variable which points to the last term of a text line ? (obviously, y can obtain that term if i knew how many terms does the line have... i.e. awk '{print $12}' ; if we are talking about a 12-terms text line) I wonder if there is an option like $?, to get the last term.
I want to append a variable string to the end of a specific line. not like append the same string to each line. like in my file i have 4 columns, i want to add a string in 5th column in some fixed row.
I'm using sed to remove certain line in a text file based on a match with 2 variables from input. Here is how it looks like in file
Philip S:Odds:45:343 Mike Junior:Odds:3:56
I prompt for 2 inputs in variable form which is compared to the first 2 fields of the above text (: seperated). So say i enter Philip S and Odds then it should delete the entire first line.
But the variable $sentence can not be identified in ' ' . And also you can see I just want to update the old file. But the sed command can not save the file for me ,so I need to write them to a new file and over write the new file .
I am writing a bash script to run everyday and output results to a file. When the same results are produced i want to overwrite the line from the previous day. (Or remove and add). So if the script finds a variable in a line. i want it to output the results to that line . sed -i did not work for me; sed: couldn't open temporary file ./sedTvOCEg: Permission denied
I am looking for a clue in shell or ant script, where I excecute a binay file on linux. For example ./myfile.bin which ask me few questions.
./myfile.bin ...........................100%
I would like to automate this process where I want to pass the hostname as a variable or read from a file is it possible? If yes any sample`s on this. I can do if this was a shell script ($1) but not sure when its binary.
I want to access a file, and check the length of every line.After, i want to check and replace all lines with length over 10 characters, with a message.Does anyone have a clue on that?
I am loading the file in Fortran. File looks something like this (shown below) I am interested in Velocity values and not Pressure values. Is there a way to code in Fortran which finds the staring LINE of Velocity values and ending LINE of values or I have to manually find the lines? IN this case it should return Starting line : 9 Ending line: 11