/* read.c - read */

#include 

/*------------------------------------------------------------------------
 *  read  -  Read one or more bytes from a device
 *------------------------------------------------------------------------
 */
syscall read(
          did32         descrp,         /* Descriptor for device        */
          char          *buffer,        /* Address of buffer            */
          uint32        count           /* Length of buffer             */
        )
{
        intmask         mask;           /* Saved interrupt mask         */
        struct dentry   *devptr;        /* Entry in device switch table */
        int32           retval;         /* Value to return to caller    */

        mask = disable();
        if (isbaddev(descrp)) {
                restore(mask);
                return SYSERR;
        }
        devptr = (struct dentry *) &devtab[descrp];
        retval = (*devptr->dvread) (devptr, buffer, count);
        restore(mask);
        return retval;
}