Reference

Tcl_CreateCloseHandler(3tcl)

arrange for callbacks when channels are closed


        
    

    
        

NAME

Tcl_CreateCloseHandler, Tcl_DeleteCloseHandler - arrange for callbacks when channels are closed

SYNOPSIS

#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.


        
    


            

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(
        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(3tcl), Tcl_Close(3tcl), Tcl_UnregisterChannel(3tcl)

KEYWORDS

callback, channel closing

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