Tcl_CreateCloseHandler man page

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.

See Also

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


callback, channel closing

Referenced By

The man page Tcl_DeleteCloseHandler(3) is an alias of Tcl_CreateCloseHandler(3).

7.5 Tcl Library Procedures