I'm new to linux world, I need to do these steps :

1)
compile this module (hello.c):

Code:
    #include <linux/module.h>
    #include <linux/kernel.h>
    #include <linux/proc_fs.h>
    
    struct proc_dir_entry *file;
    
    ssize_t proc_read(char *buffer, char **buffer_location,
    		  off_t offset, int buffer_length, int *eof, void *data) {
      int len = 0; 
    
      if (offset > 0) {
        *eof = 1;
        return len;
      }
    
      len = sprintf(buffer, "Hello, World!\n");
      return len;
    }
    
    
    int init_module(void) {
      int rv = 0;
      file = create_proc_entry("hello", 0644, NULL);
      file->read_proc = proc_read;
      file->mode = S_IFREG | S_IRUGO;
      file->uid = 0;
      file->gid = 0;
      file->size = 37;
    
      if (file == NULL) {
        rv = -ENOMEM;
        remove_proc_entry("hello", NULL);
        printk("Problem with the module!\n");
      } else {
        printk("Module loaded!\n");
      }
    
      return rv;
    }
    
    void cleanup_module(void) {
      remove_proc_entry("hello", NULL);
      printk("Module unloaded!\n");
    }
    
    MODULE_LICENSE("GPL");
2)
This module should create a file /proc/hello (where I found this file ?) when readed, this file should present the follow message: 'Hello World!'.

3)
Change the module above to show the PID instead the 'Hello World!'message.
Compile and see its working.

I'm folling this [tutorial][1], but nothing so far.

Any tip, any help will be very appreciated.


[1]: http://www.cyberciti.biz/tips/compil...el-module.html