1 #include linux/module.h
 2 #include linux/kernel.h
 3 #include linux/proc_fs.h
 4 #include linux/sched.h
 5 #include asm/uaccess.h
 6
 7 #define STRINGLEN 1024
 8
 9 char global_buffer[STRINGLEN];
10
11 struct proc_dir_entry *example_dir, *hello_file;
12
13 int proc_read_hello(char *page, char **start, off_t off, int count, int *eof,
14                 void *data) {
15         int len;
16         len = sprintf(page, global_buffer); //把global_buffer的内容显示给访问者
17         return len;
18 }
19
20 int proc_write_hello(struct file *file, const char *buffer, unsigned long count,
21                 void *data) {
22         int len;
23
24         if (count = STRINGLEN)
25                 len = STRINGLEN – 1;
26         else
27                 len = count;
28
29         copy_from_user(global_buffer, buffer, len);
30         global_buffer[len] = \0′;
31         return len;
32 }
33
34 static int __init proc_test_init(void) {
35         example_dir = proc_mkdir("proc_test", NULL);
36         hello_file = create_proc_entry("hello", S_IRUGO, example_dir);
37         strcpy(global_buffer, "hello");
38         hello_file->read_proc = proc_read_hello;
39         hello_file->write_proc = proc_write_hello;
40         return 0;
41 }
42
43 static void __exit proc_test_exit(void) {
44         remove_proc_entry("hello", example_dir);
45         remove_proc_entry(“proc_test”, NULL);
46 }
47
48 module_init(proc_test_init);
49 module_exit(proc_test_exit);