RTEMS 4.0.0 On-Line Library

I/O Manager IO_CONTROL - Special device services

RTEMS C User's Guide

15.4.8: IO_CONTROL - Special device services

CALLING SEQUENCE:

rtems_status_code rtems_io_control(
  rtems_device_major_number  major,
  rtems_device_minor_number  minor,
  void                      *argument
);

DIRECTIVE STATUS CODES:

RTEMS_SUCCESSFUL - successfully initialized
RTEMS_INVALID_NUMBER - invalid major device number

DESCRIPTION:

This directive calls the device driver I/O control routine specified in the Device Driver Table for this major number. The exact functionality of the driver entry called by this directive is driver dependent. It should not be assumed that the control entries of two device drivers are compatible. For example, an RS-232 driver I/O control operation may change the baud rate of a serial line, while an I/O control operation for a floppy disk driver may cause a seek operation.

NOTES:

This directive may or may not cause the calling task to be preempted. This is dependent on the device driver being invoked.

RTEMS C User's Guide