DOKK / manpages / debian 12 / tcl8.6-doc / Tcl_CreateCloseHandler.3tcl.en
Tcl_CreateCloseHandler(3tcl) Tcl Library Procedures Tcl_CreateCloseHandler(3tcl) 







Tcl_CreateCloseHandler, Tcl_DeleteCloseHandler - arrange for
    callbacks when channels are closed








#include <tcl.h>

void
Tcl_CreateCloseHandler(channel, proc, clientData)

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








callback, channel closing







  

    7.5
    Tcl