<TITLE>ioctl</TITLE> <body bgcolor="#ffffcc"> <hr> <pre> <h3>IOCTL(2) Linux Programmer's Manual IOCTL(2) </h3> <h3>NAME </h3> ioctl - control device <h3>SYNOPSIS </h3> #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.] <h3>DESCRIPTION </h3> 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. <h3>RETURN VALUE </h3> On success, zero is returned. On error, -1 is returned, and errno is set appropriately. <h3>ERRORS </h3> 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. <h3>HISTORY </h3> An ioctl function call appeared in Version 7 AT&T UNIX. </pre> <hr> <h3>SEE ALSO </h3><p> <a href=execve.htm>execve</a>, <a href=fcntl.htm>fcntl</a>, <a href=mt+4>mt</a>, <a href=sd+4>sd</a>, <a href=tty+4>tty</a>, <pre> <h3>BSD Man Page 23 July 1993 1 </h3> </pre> <P> <hr> <p> <center> <table border=2 width=80%> <tr align=center> <td width=25%> <a href=../index.htm>Top</a> </td><td width=25%> <a href=../master_index.html>Master Index</a> </td><td width=25%> <a href=../SYNTAX/keywords.html>Keywords</a> </td><td width=25%> <a href=../FUNCTIONS/index.htm>Functions</a> </td> </tr> </table> </center> <p> <hr> This manual page was brought to you by <i>mjl_man V-2.0</i>
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