IOCTL(2) BSD System Calls Manual IOCTL(2)

NAME
     iiooccttll - control device

SYNOPSIS
     ##iinncclluuddee <>

     int
     iiooccttll(int fildes, unsigned long request, ...);

DESCRIPTION
     The iiooccttll() function manipulates the underlying device parameters of spe-
     cial files.  In particular, many operating characteristics of character
     special files (e.g. terminals) may be controlled with iiooccttll() requests.
     The argument fildes must be an open file descriptor.

     An  ioctl request has encoded in it whether the argument is an ``in''
     parameter or ``out'' parameter, and the size of the argument argp in
     bytes.  Macros and defines used in specifying an ioctl request are
     located in the file .

RETURN VALUES
     If an error has occurred, a value of -1 is returned and errno is set to
     indicate the error.

EERRRROORRSS
     IIooccttll() will fail if:

     [EBADF]            fildes is not a valid descriptor.

     [EINVAL]           Request or argp is not valid.

     [ENOTTY]           fildes is not associated with a character special
                        device.

     [ENOTTY]           The specified request does not apply to the kind of
                        object that the descriptor fildes references.

SEE ALSO
     cdio(1), chio(1), mt(1), execve(2), fcntl(2), intro(4), tty(4)

HISTORY     An iiooccttll() function call appeared in Version 7 AT&T UNIX.

4th Berkeley Distribution      December 11, 1993     4th Berkeley Distribution