C :: Read Contents Of A File Using Low I/O Read Statements
May 15, 2013
I want to read the contents of a file block (512 bytes) by block using low I/O read statements. Each record is 64 bytes long and has a pre-defined structure. The first 4 bytes are an unsigned integer; the next 20 bytes are ascii text, etc.
I have a buffer which I can access with buf[0] to buf[63] to read the first record and then buf[64] to buf[127] for the second, etc. However, I was wondering how to map a record so that I can refer to an integer as an integer and a float as float, etc. I can't create a struct and move the 64 bytes to it, as I will have alllignment/padding problems.
What is the standard way to deal with records in C?
I have written the following code but i am stuck. Write a program that will prompt the user for a file name and open that file for reading. Print out all the information in the file, numbering each new line of text.
Code: #include <stdio.h> #include <stdlib.h> #include <conio.h> #include <ctype.h> int main() { char line[81], filename[21], c; int i = 1; FILE *inFile;
am trying to create a service that will try to create a service that will monitor a folder. Whenever a new file gets created, I am trying to read the contents of new file and copy contents (with same file) at a new location.
The problem I am facing is that only first file that gets its name copied and a file created at a new location, but without any contents. The subsequent files do not get created at all.
My Services.cs looks like this:-
public partial class Service1 : ServiceBase { public Service1() {
I am trying to read enormous binary files (10-100GB) and parse their contents a bit at a time. As part of the process I need to get the size of the file in bytes. The simple solution
Code: fseek(file,0,SEEK_END); size=ftell(file);
fails because the file size overflows the long int type returned by ftell. I need a long long int.
Is there a reasonably efficient way to do this? The good news is that it only needs to be done once. I suppose I could read it one character at a time until I hit the end and keep count, but that just seems inelegant...
Is possible read text form keyboard using read() function? or which is best way in ansi creplace input command form basic language. for numbers and text...
I'm working on a program that reads from a .dat file that has names and numbers associated with the name. What the big picture it will be able to take those names and numbers find the avg of certain peoples scores and display these numbers or names who have the highest etc.
So to keep this short in my main I have it call the class and pass "Even.dat" as a char * fname my questions is how do I go about reading this .dat file? I know sorting it will use a sort algorithm which I will be using a bubble sort. But I haven't worked with ofstream and ifstream very much so some tips would be great! Here's an example of what the .dat file contains
David 42 Rebecca 83 Jonathan 79 Matthew 77 Rose 7 Melanie 75 int main() { StudentStat StatEven("Even.dat");
I am a learner in C#. I want to read a particular value from the CSV file. I have learned the getting the csv file into a datatable through browsing. See the following code and my CSV file format. The following code displays all the values.... Say, I want to get what is the 'Volume' for 'ID' = 90.
Code: using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; using System.IO; using System.Data;
I have a code for reading a series of data from a text file.The code was shown below I don't know why I can't successfully read file. (Can open successfully)
btw: the text file and source code were located at the same directory.
#include <stdio.h> #include <stdlib.h> int main(){ int numOfAtoms;
The Objective Of This Program Is To Create A File To Write Text And Read Back The File Content. To Do That I Have Made Two Function writeFile() To Write And readFile() To Read.The readFile() function works just fine but writeFile() doesn't.
How writeFile() function Works? when writeFile() function Execute It Takes Characters User Type And When Hit Enter(ASC|| 10) It Ask "More?(Y/N)" That Means What User Want? Want To Go Next Line Or End Input?
If "Y" Than Inputs Are Taken From Next Line Else Input Ends.
But The Problem Is When Program Encounters ch==10 It Shows "More?(Y/N)" And Takes Input In cmd variable.If cmd=='Y' I Mean More From Next Line Than It Should Execute Scanf Again To Take ch I Mean User Input.But Its Not!!! Its Always Showing "More?(Y/N)" Again And Again Like A Loop.
Code: #include <stdio.h> void writeFile(void); void readFile(void); int main(){
I am writing a simple file/text parser to read a config file for some code I am working on. It's dead simple and not particularly smart but it should get the job done. The code reads a config file:
Here is where it gets wierd. You'll notice that there is an unused variable (filepath) in the config struct. This variable is not referenced or used anywhere in the code, ever. Yet if I comment out the declaration of char filepath[1024], the code segfaults partway through the read_config() function.
My best guess is that there is a buffer overflow elsewhere and it just so happens that the memory allocated for filepath happened to be there to catch it up until now, but I can't work out where it might be happening. With the declaration commented out, the read_config() function gets as far as reading the "padding" variable before it crashes. Yet when the declaration is there, then all the variabled are read correctly and everything seems to work.
I have a .txt file which I want to read from and then write a new text file, this time with sorted lines. It is easy to sort one value, but what about sorting entire lines based on one value?
I want to sort the lines based on the FIRST value.
When reading a binary .img why is it when you read it by slurping in the file, then save it to a string and cout, you don't see the binary but random garbage?
I have learnt recently how to use fgetc, fputc, fputs, fgets but still I am not able to figure out how to read values from a file like for example:
12 14 1928 32993932 17 98 166 109 201
These are separate integers & i want to read them and then manipulate these individual integers like going for 2*I1, 4*I2 and so on where I1 and I2 are 12 & 14.
I'm stuck on unix system programming and am beginner about it. Assume that there is a directory which X. There are a file(text1.txt) and another directory which is Y in X. Last, there are two files(text2.noExtension) and text3.noExtension) and another directory which is Z in Y. My goal is that read files and enter directories until there is no directory. How to go on. Example:
Code:
#include <stdio.h> #include <dirent.h> int main (int c, char *v[]) { struct dirent *pDirent; DIR *pDir; if (c < 2) { printf ("Usage: testprog <dirname>"); return 1;
I'm new with C language. I got task to do . Actually there are 2 points. Both should be done with reading text from file. write down all letters from text in reverse alphabetic order (each letter 1 time).write down all words in random order.
I'm stuck with first point. Below code gives me entire text, but i need unique characters only. Text file contains few sentences.
Code: #include<stdio.h> void main( ) { FILE *in; int ch; if ( (in = fopen("test.txt", "r") ) != NULL ) {
