ioctl(2)                                                 ioctl(2)



NAME
     ioctl -  requests  low-level,  input/output  operations  for
     specific devices

SYNOPSIS
     int ioctl( fildes, request, arg)
     int fildes, request;

DESCRIPTION
     ioctl can perform a variety of functions on devices that are
     referenced through their character (raw) device files.
     Section 7 describes the ioctl requests that apply to each
     device.

STATUS MESSAGES AND VALUES
     If an error has occurred, a value of -1 is returned and
     errno is set to one of the following values to indicate the
     error:

     EBADF
          fildes is not a valid open file descriptor.

     ENOTTY
          fildes is not associated with a character special
          device.

     EINVAL
          request or arg is not valid for the associated device.
          See Section 7.

     EINTR
          A signal was caught during the ioctl system call.

SEE ALSO
     fcntl(2), intro(2), fd(7), gd(7), intro(7), mtio(7),
     termio(7)



















January 1992                                                    1