.z.wc:f

Where

• f is a unary function
• h is the handle to a websocket connection to a kdb+ session

f[h] is evaluated after a websocket connection has been closed. (Since V3.3t 2014.11.26.)

As the connection has been closed by the time .z.wc is called, there are strictly no remote values that can be put into .z.a, .z.u or .z.w so the local values are returned.

This allows you to clean up things like tables of users keyed by handle.