Tcl 9.0/Tk9.0 Documentation > Tcl C API, version 9.0.0 > CrtCloseHdlr

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NAME

Tcl_CreateCloseHandler, Tcl_DeleteCloseHandler — arrange for callbacks when channels are closed

SYNOPSIS

#include <tcl.h>
Tcl_CreateCloseHandler(channel, proc, clientData)
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.

void *clientData (in)

Arbitrary one-word value to pass to proc.

DESCRIPTION

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(
        void *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, Tcl_Close, Tcl_UnregisterChannel

KEYWORDS

callback, channel closing