DATAGRAM_CHAN_P  4801 src/process.c        if (DATAGRAM_CHAN_P (inchannel))
DATAGRAM_CHAN_P  6149 src/process.c    if (DATAGRAM_CHAN_P (channel))
DATAGRAM_CHAN_P  6643 src/process.c  	  if (DATAGRAM_CHAN_P (outfd))