Determines what error occurred, if any, after calling a Resource Manager function.

OSErr ResError ();

function result

A result code. If no error occurred, the function returns noErr. If an error occurs at the Resource Manager level, the function returns one of the result codes specific to the Resource Manager. If an error occurs at the Operating System level, the function returns an Operating System result code. In certain cases, the ResError function returns noErr even though a Resource Manager function was unable to perform the requested operation. See the individual function descriptions for details about the circumstances under which this happens.

DISCUSSION

Resource Manager functions do not report error information directly. Instead, after calling a Resource Manager function, your application should call this function to determine whether an error occurred. You also can use this function to check for an error after application startup (system software opens the resource fork of your application during application startup).

Resource Manager functions usually return NULL or –1 as the function result when there’s an error. For Resource Manager functions that return –1, your application can call the ResError function to determine the specific error that occurred. For Resource Manager functions that return handles, your application should always check whether the value of the returned handle is NULL. If it is, your application can use this function to obtain specific information about the nature of the error. Note, however, that in some cases ResError returns noErr even though the value of the returned handle is NULL.

AVAILABILITY

Supported in Carbon. Available in Mac OS 8.1 and later when Carbon 1.0.2 or later is present.

© 2000 Apple Computer, Inc. — (Last Updated 5/8/2000)