Programming :: Programing - Reading File Line By Line Then Char By Char In Each Line
May 29, 2010
I've never programed shell scripting.
Code goes like so:
I simply want to read a file "data.txt" line by line Then char by char and add them into a result var. The file is supossed to always contain numeric values
Greetings, I have installed a VMware host on Windows 7 64bit and followed with a 10.04LTS 64 bit guest install. Everything went smooth. I have used VMware before, but the other way around.. Linux host and Windows guest.
So this time I am installing the VMWare tools on the guest, ubuntu 10.04, but it seems to be failing. The vmware tools install ran fine the first time with no errors, but I was getting the follwoing error after logging into the Ubuntu guest afterwards.
Could Not Apply the Start Configuration for Monitors Error Line 1: Char 1 Whitespace or empty file
So I re installed the VMware tools once again, but still the same.
I am hoping that someone here has come across this before and hs a workaround. I don't think the vmware tools was installed correctly.
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?
Just in case someone can reply a silly question, I've quite forgot the vi/vim command to bring the cursor to the 1st char in the current line. I do remember that for bringing it to EOL is '$'.
I have two files, file1.traj and file2.traj. Both these files contain identical data and the data are arranged in same format in them. The first line of both files is a comment.
At line 7843 of both files there is a cartesian coordinate X, Y and Z ( three digits ). And at line 15685 there is another three digits. The number of lines in between two cartesian coordinates are 7841. And there are few hundreds of thousands of lines in a file.
What I need to do is copy the X Y Z coordinate (three digits) from file1.traj at line 7843 and paste into file2.traj at the same line number as in file1.traj. The next line will be 15685 from file1.traj and replace at line 15685 at file2.traj. And I dont want other lines (data) in file2.traj get altered. This sequence shall be going on until the end of the file. Means copy and substitude the selected lines from file1.traj into file2.traj.
I tried to use paste command but I cant do for specified line alone.
Here i showed the data format in the file. I used the line number for clarity purpose.
Programming in C.I have two char arrays.char buf1[1024];char buf2[1024];Aren't buf1 and buf2 also pointers?I read in 1024 bytes into buf1 which contain about 300 bytes of characters with newlines. The data is basically a few English sentences. I'm trying to scan buf1 for newlines and then stop at the 1st newline and copy the rest of the data from that 1st newline into buf2.So I run a for loop to look for that new line.
I have a project due for my Intro to C++ class and we are suppose to generate a file listing that will take an input of a C++ source code with .cpp extension and make a copy of it with a .lst extention that will have a line number preceding each and every line.
I am trying to write a program in C which compares two files and prints the line that is equal.
Here file1.txt has
and file2.txt has
Note: file2.txt consist of only a single string where as file2.txt has multiple lines. Actually im comparing two files with md5sum values.
Here is the code but it compares only first line of files..but it should compare the whole file1..and sorry iam a beginner in C can any1 sujest some modification to this code so that..it can compare file2 with entire file1
Line 43 points at the snprintf() command.I think the error has to do with the function being virtual and the const after the function definition, however although I have been looking really hard I have not being able to find the reason nor the solution to the problem.
One workaround that I know is moving the block of source withing the virtual function, in the constructor, however having read around (boost library exceptions tutorials) it specifically said that formating of errors messages should not take place withing the construction of objects because we are risking throwing an exceptions and messing up the flow order.
i define variable of type char (range -128 to 127). when i tried to print the value after assigning a -ve value to it it displaying a +ve value of that -ve value(256+value).
I wish to add information to one of my files based on matching IDs,
Here is an example
(the id is the 3 colunm)
(the ID is the 2 colunm)
And the output i wish to be
OUTPUT:
So as you can see the ones that do not match are still present, and the ones that do match just have the extra information from file2.txt added to them.
I thought about using join but that only seems to join the ones that match displays thoes only. i would like all the information in the output file.
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:
Was wondering if any perl guru's could help me with a quick log file adjustment. I have a text file that looks like so (tabs and newlines are revealed so you can see what separates the data):
There are maybe 100 lines of text in this file at any given time. I need to delete all duplicate lines only looking at the first bit of text prior to the first tab. It doesn't matter which one gets deleted as long as there are no two lines that begin with that same text at the beginning before the first tab. So in this example, either the fist line "1234" or the last line "1234" would need to be deleted. I already have code in my script that opens the files - I just need the code to read the text into an array and the part that would find matches based on the above criteria, and make the deletions.
If it would be easier, I can even do a system call and use SED (v4.1.5) and/or AWK (3.1.5) instead.
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?
In C, I want to make a program that will take a file and replace it with a file that's nearly the same but with some minor changes. Also, I would like to point out that I'm still fairly much a beginner with C. As for an example of the file, I want to take something like this:
Code:
Random Crap More Random Crap Even More Something That Changes XXXXX
[code]....
I figured the best way to go about doing this was to open the file and a blank file, read the original bit by bit and when it gets to the point that needs to be changed exchange the part that needs to be changed with what it should be changed to, delete the original file, and rename the new one to the correct name. So the first problem I've run into (and I'll probably have more) is that when I'm trying to read stuff from the original file, my program doesn't seem to be finding the original. I'm sure much of my problems will be just from not knowing how to use the C functions so bear with me. Right now I have the following:
Died Here: No such file or directory Segmentation fault
Right now the length of 50 was just a random test length. Pretty much I was just trying to get it to read anything from the file. In the end I'm going to want it to read the entire file bit by bit, but at the moment I can't seem to get it to read anything.
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.
I need to run a command in a shell script to insert a line in a file, after it finds certain line. To add the line 'user = mysql' after the line [mysqld] in file /etc/my.cnf
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.
going back to my earlier post "Last digit minus ONE", when i get a Ip addresse with minus 1 ($ip), i need to add the new Ip address ($ip) to resolv.conf of that system. so from resolve.conf: