Tcl_CreateCloseHandler(3) Tcl Library Procedures Tcl_CreateCloseHandler(3)

Tcl_CreateCloseHandler, Tcl_DeleteCloseHandler - arrange for callbacks when channels are closed

#include <tcl.h>

Tcl_CreateCloseHandler(channel, proc, clientData)

Tcl_DeleteCloseHandler(channel, proc, clientData)

Tcl_Channel channel (in)
The channel for which to create or delete a close callback.
Tcl_CloseProc *proc (in)
The procedure to call as the callback.
ClientData clientData (in)
Arbitrary one-word value to pass to proc.

Tcl_CreateCloseHandler arranges for proc to be called when channel is closed with Tcl_Close or Tcl_UnregisterChannel, or using the Tcl close command. Proc should match the following prototype:

typedef void Tcl_CloseProc(
        ClientData clientData);

The clientData is the same as the value provided in the call to Tcl_CreateCloseHandler.

Tcl_DeleteCloseHandler removes a close callback for channel. The proc and clientData identify which close callback to remove; Tcl_DeleteCloseHandler does nothing if its proc and clientData arguments do not match the proc and clientData for a close handler for channel.

close(n), Tcl_Close(3), Tcl_UnregisterChannel(3)

callback, channel closing

7.5 Tcl