tcl7.6 C API - CrtCloseHdlr






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 call-
                                              back.

     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  fol-
     lowing 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)



KEYWORDS

     callback, channel closing