On Tue, 2005-03-29 at 16:18 +0530, Dhanashri Bhate wrote:
> > static ssize_t Device_read(struct file *filp,char *buf,size_t
> > count,loff_t *offset)
> > {
> > if (*offset >= sizeof(msg) )
> > {
> > return 0;
> > }
> >
> > count = sizeof(msg);
> >
> > if(copy_to_user(buf, msg, count))
> > return -EFAULT;
> >
> > *offset += count;
> > return count;
> > }
> >
>
>
> Well.. i had similar program some time back, which worked fine.
> I guess the problem is with the --first call-- to the read function where you are assuming that the value will be >= message size. Try printing out there itself what is the value of "offset" is!
>
first time >>>>>>> offset = 0;
second time >>>>>> offset = 6; (total size of string including '\0')
so it's fine here.
-mandeep
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