bionic (3) tkwait.3tk.gz

NAME

       tkwait - Wait for variable to change or window to be destroyed

SYNOPSIS

       tkwait variable name

       tkwait visibility name

       tkwait window name
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DESCRIPTION

       The  tkwait  command  waits for one of several things to happen, then it returns without taking any other
       actions.  The return value is always an empty  string.   If  the  first  argument  is  variable  (or  any
       abbreviation  of  it) then the second argument is the name of a global variable and the command waits for
       that variable to be modified.  If the first argument is visibility (or any abbreviation of it)  then  the
       second argument is the name of a window and the tkwait command waits for a change in its visibility state
       (as indicated by the arrival of a VisibilityNotify event).  This form is typically used  to  wait  for  a
       newly-created  window to appear on the screen before taking some action.  If the first argument is window
       (or any abbreviation of it) then the second argument is the name of a window and the tkwait command waits
       for  that  window  to be destroyed.  This form is typically used to wait for a user to finish interacting
       with a dialog box before using the result of that interaction.

       While the tkwait command is waiting it processes events in the normal fashion, so  the  application  will
       continue  to  respond to user interactions.  If an event handler invokes tkwait again, the nested call to
       tkwait must complete before the outer call can complete.

SEE ALSO

       bind(3tk), vwait(3tk)

KEYWORDS

       variable, visibility, wait, window