![Trending Articles on Technical and Non Technical topics](/images/trending_categories.jpeg)
Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Iseek() in C/C++ to read the alternate nth byte and write it in another file
In this tutorial, we will be discussing a program to understand how to read the alternate nth byte and write it in another file.
For this, we will be provided with two .txt files. Our task is to write the contents from one file to another file using Iseek() which is used to change the pointer of the file descriptor.
Example
#include <stdio.h> #include <unistd.h> #include <sys/types.h> #include <fcntl.h> void func(char arr[], int n){ int f_write = open("start.txt", O_RDONLY); int f_read = open("end.txt", O_WRONLY); int count = 0; while (read(f_write, arr, 1)){ if (count < n) { lseek (f_write, n, SEEK_CUR); write (f_read, arr, 1); count = n; } else{ count = (2*n); lseek(f_write, count, SEEK_CUR); write(f_read, arr, 1); } } close(f_write); close(f_read); } int main(){ char arr[100]; int n; n = 5; func(arr, n); return 0; }
Output
(First file)
(Output file)
Advertisements