taglinefilesource code
_IO46include/asm-alpha/ioctl.h#define _IO(type,nr)    _IOC(_IOC_NONE,(type),(nr),0)
_IO56include/asm-i386/ioctl.h#define _IO(type,nr)    _IOC(_IOC_NONE,(type),(nr),0)
_IO41include/asm-ppc/ioctl.h#define _IO(type,nr)    _IOC(_IOC_NONE,(type),(nr),0)
_IO33include/asm-sparc/ioctl.h#define _IO(type,nr)        _IOC(_IOC_NONE,(type),(nr),0)
_IO103include/linux/soundcard.h#define  _IO(x,y)  ((int)(IOC_VOID|(x<<8)|y))