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以下是sample code.. test_read 回傳值表示還有多少需要讀取 test_write 回傳值表示已經處理了幾個byte #include #include #include #define TESTNAME "foo" #define MAXLENGTH 64 static int test_read(char *page, char **start, off_t off, int count, int *eof, void *data) { // return value means the remaining bytes need to read return count; } static int test_write(struct file *file, const char *buffer, unsigned long count, void *data) { char tmp[128]; int t1 = 0; if (!count) return 0; if ( count > MAXLENGTH ) return -EINVAL; if (buffer && !copy_from_user(tmp, buffer, 128)) { sscanf(tmp, "%x", &t1); printk("t1 = 0x[%x]\n", t1); } else{ return -EFAULT; } return count; } static int __init test_init(void) { struct proc_dir_entry *test_proc; test_proc = create_proc_entry( TESTNAME, 0644, NULL); if (test_proc == NULL) { remove_proc_entry(TESTNAME, NULL); printk(KERN_ALERT "Error: Could not initialize /proc/%s\n", VTESTNAME1); return -ENOMEM; } test_proc->read_proc = (read_proc_t *)test_read; test_proc->write_proc = (write_proc_t *)test_write; printk("/proc/%s created\n", TESTNAME); return 0; } static void __exit test_exit( void ) { remove_proc_entry( VTESTNAME, NULL ); } module_init( test_init ); module_exit( test_exit );