Function - Read a sequence of bytes from a specific device.
#include<device/device.h>
kern_return_t device_read
(device_t device,
mach_port_t reply_port,
dev_mode_t mode,
recnum_t recnum,
io_buf_len_t bytes_wanted,
io_buf_ptr_t io_buf_ptr_t,
mach_msg_type_number_t mach_msg_type_number_t);
#include<device/device_request.h>
kern_return_t device_read_request
(mach_port_t device,
mach_port_t reply_port,
dev_mode_t mode,
recnum_t recnum,
io_buf_len_t bytes_wanted);
kern_return_t ds_device_read_reply
(mach_port_t reply_port,
kern_return_t return_code,
io_buf_ptr_t data,
mach_msg_type_number_t data_count);
The device_read function reads a sequence of bytes from a device object. The meaning of recnum as well as the specific operation performed is device dependent.
Only generic errors apply.
Functions: device_read_inband, device_read_overwrite, device_reply_server.