IOCTL(2) Linux Programmer's Manual IOCTL(2)
NAME
ioctl - control deviceSYNOPSIS
#include <sys/ioctl.h> int ioctl(int d, int request, ...) [The "third" argument is traditionally char *argp, and will be so named for this discussion.]DESCRIPTION
The ioctl function manipulates the underlying device parameters of special files. In particular, many operat- ing characteristics of character special files (e.g. ter- minals) may be controlled with ioctl requests. The argu- ment d 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 speci- fying an ioctl request are located in the file sys/ioctl.h.RETURN VALUE
On success, zero is returned. On error, -1 is returned, and errno is set appropriately.ERRORS
EBADF d is not a valid descriptor. ENOTTY d is not associated with a character special device. ENOTTY The specified request does not apply to the kind of object that the descriptor d references. EINVAL Request or argp is not valid.HISTORY
An ioctl function call appeared in Version 7 AT&T UNIX.
BSD Man Page 23 July 1993 1
Top | Master Index | Keywords | Functions |