tag	line	file	source code
FIONREAD	44	fs/ioctl.c	case FIONREAD:
FIONREAD	140	fs/pipe.c	case FIONREAD:
FIONREAD	35	include/linux/termios.h	#define TIOCINQ    FIONREAD
FIONREAD	964	net/inet/tcp.c	case FIONREAD: