Simple Misc Driver - Problem with string copy to user

[Lucas Tanure]

Hi!

Goal, when the user do :
# head -1 /dev/miscdrv

The driver prints:  Hello World!

Steps:
# Make
# insmod misc.ko
# head -1 /dev/miscdrv

Why my driver doesn't work ?

What is worg with my read operation?

static ssize_t
misc_drv_read(struct file *filp, char __user * buf, size_t count, loff_t *
offp){
    int nbytes;
char * string = "hello World";
nbytes = copy_to_user(buf, string, 12);
 return nbytes;
}


--
Lucas Tanure
Brazil
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