Tcl_CreateCloseHandler(3)

Tcl_CreateCloseHandler3

Arrange for callbacks when channels are closed

Usage

#include <tcl.h>

void
Tcl_CreateCloseHandler(channel, proc, clientData)

void
Tcl_DeleteCloseHandler(channel, proc, clientData)

    


    

Arguments

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.


    


            

Overview

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.

Keywords

callback, channel closing

From tcl 8.6.16-1 in Arch Linux 2026-11-01. Parsed by carta from the page's man source.