mp := acquirem()
	span.ensureSwept()

	offset := uintptr(p) - span.base()
	kind := s.kind

	lock(&span.speciallock)

	// Find splice point, check for existing record.
	iter, exists := span.specialFindSplicePoint(offset, kind)
	if !exists {
		// Splice in record, fill in offset.
		s.offset = uint16(offset)
		s.next = *iter
		*iter = s
		spanHasSpecials(span)
	}

	54:  "connection reset by peer",
	55:  "no buffer space available",
	56:  "socket is already connected",
	57:  "socket is not connected",
	58:  "can't send after socket shutdown",
	59:  "too many references: can't splice",
	60:  "operation timed out",
	61:  "connection refused",
	62:  "too many levels of symbolic links",
	63:  "file name too long",
	64:  "host is down",
	65:  "no route to host",

	132: "no buffer space available",
	133: "transport endpoint is already connected",
	134: "transport endpoint is not connected",
	143: "cannot send after socket shutdown",
	144: "too many references: cannot splice",
	145: "connection timed out",
	146: "connection refused",
	147: "host is down",
	148: "no route to host",
	149: "operation already in progress",
	150: "operation now in progress",

	54:  "connection reset by peer",
	55:  "no buffer space available",
	56:  "socket is already connected",
	57:  "socket is not connected",
	58:  "can't send after socket shutdown",
	59:  "too many references: can't splice",
	60:  "operation timed out",
	61:  "connection refused",
	62:  "too many levels of symbolic links",
	63:  "file name too long",
	64:  "host is down",
	65:  "no route to host",

	105: "no buffer space available",
	106: "transport endpoint is already connected",
	107: "transport endpoint is not connected",
	108: "cannot send after transport endpoint shutdown",
	109: "too many references: cannot splice",
	110: "connection timed out",
	111: "connection refused",
	112: "host is down",
	113: "no route to host",
	114: "operation already in progress",
	115: "operation now in progress",

	54: "connection reset by peer",
	55: "no buffer space available",
	56: "socket is already connected",
	57: "socket is not connected",
	58: "can't send after socket shutdown",
	59: "too many references: can't splice",
	60: "operation timed out",
	61: "connection refused",
	62: "too many levels of symbolic links",
	63: "file name too long",
	64: "host is down",
	65: "no route to host",
	66: "directory not empty",

	54: "connection reset by peer",
	55: "no buffer space available",
	56: "socket is already connected",
	57: "socket is not connected",
	58: "can't send after socket shutdown",
	59: "too many references: can't splice",
	60: "operation timed out",
	61: "connection refused",
	62: "too many levels of symbolic links",
	63: "file name too long",
	64: "host is down",
	65: "no route to host",
	66: "directory not empty",

	54: "connection reset by peer",
	55: "no buffer space available",
	56: "socket is already connected",
	57: "socket is not connected",
	58: "can't send after socket shutdown",
	59: "too many references: can't splice",
	60: "operation timed out",
	61: "connection refused",
	62: "too many levels of symbolic links",
	63: "file name too long",
	64: "host is down",
	65: "no route to host",
	66: "directory not empty",

	54: "connection reset by peer",
	55: "no buffer space available",
	56: "socket is already connected",
	57: "socket is not connected",
	58: "can't send after socket shutdown",
	59: "too many references: can't splice",
	60: "connection timed out",
	61: "connection refused",
	62: "too many levels of symbolic links",
	63: "file name too long",
	64: "host is down",
	65: "no route to host",
	66: "directory not empty",

	{112, "ENOATTR", "no attribute found"},
	{113, "ESAD", "security Authentication Denied"},
	{114, "ENOTRUST", "not a Trusted Program"},
	{115, "ETOOMANYREFS", "too many references: can't splice"},
	{116, "EILSEQ", "invalid wide character"},
	{117, "ECANCELED", "asynchronous I/O cancelled"},
	{118, "ENOSR", "out of STREAMS resources"},
	{119, "ETIME", "system call timed out"},