SIOCPARM_MASK 116 include/uapi/linux/soundcard.h #define _SIOR(x,y,t) ((int)(SIOC_OUT|((sizeof(t)&SIOCPARM_MASK)<<16)|(x<<8)|y)) SIOCPARM_MASK 117 include/uapi/linux/soundcard.h #define _SIOW(x,y,t) ((int)(SIOC_IN|((sizeof(t)&SIOCPARM_MASK)<<16)|(x<<8)|y)) SIOCPARM_MASK 119 include/uapi/linux/soundcard.h #define _SIOWR(x,y,t) ((int)(SIOC_INOUT|((sizeof(t)&SIOCPARM_MASK)<<16)|(x<<8)|y)) SIOCPARM_MASK 120 include/uapi/linux/soundcard.h #define _SIOC_SIZE(x) ((x>>16)&SIOCPARM_MASK)