cdev_read()

Transfer available data from the device's internal input buffer to a user-provided buffer

Synopsis:

#include <qvm/cdev.h>

int cdev_read(struct cdev_state *cds,
              uint8_t *data,
              unsigned len)

cds: A pointer to a structure with the character device state (see cdev_state).
data: A pointer to your buffer, which will receive the data.
len: The number of bytes available in the buffer.

Use this function to read data from a device's internal buffer and write it into your own buffer.

If successful, the number of bytes actually read; otherwise, a negative errno value.