Device Driver : Basic Program to make MODULE

Basic program to make the module in Kernel Space and add it into the process

Write the program with the file extension ".c" . After that, make the Makefile. Then execute the Makefile by writing make. after that insert the module in the Process by writing insmod <filename>.ko . Then check the Kernel module by writing the command dmesg|less. For removing the module from the Process write rmmod <filename>.ko.

//basic.c
#include<linux/init.h>
#include<linux/module.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("RAJ");

static int hello_init(void)
{
printk(KERN_ALERT "HELLO , THERE \n");
return 0;

}


static int hello_exit(void)
{
printk(KERN_ALERT "Goodbye everyone i m gonna find u and kill you \n");
return 0;
}

module_init(hello_init);
module_exit(hello_exit);

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Device Driver: Char Driver part 1 -> Kernel and Application Program for file handling

Tutorial :

Program in a KERNEL to be use by user for open,close,read and write, along with the USER program to access Kernel program, with make file.

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/* Program to make a kernel to be accessed by the user */
#include<linux/module.h>
#include<linux/kernel.h>
#include<linux/kdev_t.h>
#include<linux/fs.h>
#include<linux/cdev.h>
#include<asm/uaccess.h>
MODULE_LICENSE("GPL");
struct cdev rss_str;
int major=0;
int minor=0;
dev_t rss;
void rss_reg();
static int rss_init()
{
printk("intializing module\n");
rss_reg();
return 0; }
static void rss_release()
{
printk("Exiting module\n");
cdev_del(&rss_str);
unregister_chrdev_region(rss,1);
}
// READ file

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