Set options on {handle}: "callback" the channel callback "timeout" default read timeout in msec "mode" mode for the whole channel See |ch_open()| for more explanation. {handle} can be a Channel or a Job that has a Channel. Note that changing the mode may cause queued messages to be lost. These options cannot be changed: "waittime" only applies to |ch_open()| Can also be used as a |method|: GetChannel()->ch_setoptions(options)