# UnchainPanelCallback

int UnchainPanelCallback (int panel, const char typeName[]);

## Purpose

This function unchains the callback function that was linked to the control by the ChainPanelCallback function.

| Note The behavior of this function is undefined if it attempts to unlink a callback function while inside of a DIFFERENT chained callback function for the same panel.

## Parameters

Input
Name | Type | Description
panel | integer | The specifier for a particular panel that is currently in memory. This handle will have been returned by the LoadPanel, NewPanel, or DuplicatePanel function.
typeName | const char [] | Pass in the string that was passed to ChainPanelCallback. If the panel has not been previously linked by ChainPanelCallback with specified type name, then nothing is done.

## Return Value

Name | Type | Description
status | integer | Returns 1 if the callback was unchained, 0 if the type name was not found, or a negative error code if the function failed. The possible negative error codes are:
–1 to –999 | A User Interface Library error code. (Constants are available in userint.h.)
A description of any of these error codes can be obtained using the GetGeneralErrorString function in the toolbox.fp instrument driver.