projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| ab9bb6ba C |
1 | .TH IOCTL 2 "7 July 1983" |
| 2 | .UC 4 | |
| 3 | .SH NAME | |
| 4 | ioctl \- control device | |
| 5 | .SH SYNOPSIS | |
| 6 | .nf | |
| 7 | .ft B | |
| 8 | #include <sys/ioctl.h> | |
| 9 | .PP | |
| 10 | .ft B | |
| 11 | ioctl(d, request, argp) | |
| 12 | int d, request; | |
| 13 | char *argp; | |
| 14 | .fi | |
| 15 | .ft R | |
| 16 | .SH DESCRIPTION | |
| 17 | .I Ioctl | |
| 18 | performs a variety of functions | |
| 19 | on open descriptors. In particular, many operating | |
| 20 | characteristics of character special files (e.g. terminals) | |
| 21 | may be controlled with | |
| 22 | .I ioctl | |
| 23 | requests. | |
| 24 | The writeups of various devices in section 4 discuss how | |
| 25 | .I ioctl | |
| 26 | applies to them. | |
| 27 | .PP | |
| 28 | An ioctl | |
| 29 | .I request | |
| 30 | has encoded in it whether the argument is an \*(lqin\*(rq parameter | |
| 31 | or \*(lqout\*(rq parameter, and the size of the argument \fIargp\fP in bytes. | |
| 32 | Macros and defines used in specifying an ioctl | |
| 33 | .I request | |
| 34 | are located in the file | |
| 35 | .IR <sys/ioctl.h> . | |
| 36 | .SH "RETURN VALUE | |
| 37 | If an error has occurred, a value of \-1 is returned and | |
| 38 | .I errno | |
| 39 | is set to indicate the error. | |
| 40 | .SH ERRORS | |
| 41 | .I Ioctl | |
| 42 | will fail if one or more of the following are true: | |
| 43 | .TP 15 | |
| 44 | [EBADF] | |
| 45 | \fID\fP is not a valid descriptor. | |
| 46 | .TP 15 | |
| 47 | [ENOTTY] | |
| 48 | \fID\fP is not associated with a character | |
| 49 | special device. | |
| 50 | .TP 15 | |
| 51 | [ENOTTY] | |
| 52 | The specified request does not apply to the kind | |
| 53 | of object which the descriptor \fId\fP references. | |
| 54 | .TP 15 | |
| 55 | [EINVAL] | |
| 56 | \fIRequest\fP or \fIargp\fP is not valid. | |
| 57 | .SH "SEE ALSO" | |
| 58 | execve(2), fcntl(2), mt(4), tty(4), intro(4N) |