speaker.h

来自「基于组件方式开发操作系统的OSKIT源代码」· C头文件 代码 · 共 32 行

/*
 * speaker.h -- interface definitions for speaker ioctl()
 *
 * v1.4 by Eric S. Raymond ([e-mail]) Aug 1993
 *      modified for FreeBSD by Andrew A. Chernov <[e-mail]>
 *
 */

#ifndef _SPEAKER_H_
#define _SPEAKER_H_

#include <sys/ioctl.h>

#define SPKRTONE        _IOW('S', 1, tone_t)    /* emit tone */
#define SPKRTUNE        _IO('S', 2)             /* emit tone sequence*/

typedef struct
{
    int	frequency;	/* in hertz */
    int duration;	/* in 1/100ths of a second */
}
tone_t;

/*
 * Strings written to the speaker device are interpreted as tunes and played;
 * see the spkr(4) man page for details.
 */

#endif /* _SPEAKER_H_ */

/* speaker.h ends here */