Help Reqd: "uiomove" transferring zero bytes from user-kernel space

[rashmi ns]

Sorry ,
           uiomove does not written no of bytes copied from user_space
to kernel space or from kernel space to userspace .My understanding
was wrong .
uiomove returns 0 on success .
Regards,
Rashmi


On 12/12/05, rashmi ns <nsrashmi at gmail.com> wrote:
> Hello Team,
>                   when i use  "uiomove"  in the character device
> interface the no of bytes transfrerred between kernel and userspace is
> zero .but the actual data transferred when trraced through
> "uio->resid" is correct .can  any one explain why this is happening ?
>
> /*Character Device Interfaces*/
> static struct cdevsw  hdlc_cdevsw = {
>
>         .d_maj      = CDEV_MAJOR,
>         .d_open     = hdlc_open,
>         .d_read     = hdlc_read,
>         .d_write     = hdlc_write,
>         .d_ioctl    = hdlc_ioctl,
>         .d_close    = hdlc_close,
>         .d_version  = D_VERSION,
> };
> static int hdlc_write(dev_t dev, struct uio *uio, int ioflag)
> {
>         int     towrite,written;  /*char device inf*/
>      written=uiomove((void *)write_tx_buffer,towrite,uio);
>      uprintf("uio->resid=%d",uio->uio_resid);
>     uprintf("No of bytes written  =%d",written);
>
>
>
>
> }
>
> Thanks and Regards,
> Rashmi.N.S
>