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<a name="tkwait-1"></a>
<h3 class="section">3.22 tkwait</h3>
<p>tkwait \- Wait for variable to change or window to be destroyed
</p><a name="Synopsis-34"></a>
<h4 class="unnumberedsubsec">Synopsis</h4>
<br><p><b>tkwait :variable </b><i>name</i><!-- /@w --><br>
<br><b>tkwait :visibility </b><i>name</i><!-- /@w --><br>
<b>tkwait :window </b><i>name</i>
</p>
<a name="Description-33"></a>
<h4 class="unnumberedsubsec">Description</h4>
<p>The <b>tkwait</b> 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 <b>:variable</b> (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 <b>:visibility</b> (or any abbreviation
of it) then the second argument is the name of a window and the
<b>tkwait</b> 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 <b>:window</b> (or any abbreviation
of it) then the second argument is the name of a window and the
<b>tkwait</b> 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.
</p>
<p>While the <b>tkwait</b> command is waiting it processes events in
the normal fashion, so the application will continue to respond
to user interactions.
</p>
<a name="Keywords-36"></a>
<h4 class="unnumberedsubsec">Keywords</h4>
<p>variable, visibility, wait, window
</p>
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