Writes resource data in memory immediately to a file’s resource fork.

void WriteResource (
    Handle theResource
);

theResource

A handle to a resource. The function checks the resChanged attribute of this resource. If the resChanged attribute is set to 1, such as after a successful call to the ChangedResource or AddResource function, WriteResource writes the resource data in memory to the resource fork, then clears the resChanged attribute in the resource’s resource map in memory.

If the resource is purgeable and has been purged, the function writes zero-length resource data to the resource fork. If the resource’s resProtected attribute is set to 1, the function does nothing, and the ResError function returns the result code noErr. The same is true if the resChanged attribute is not set (that is, set to 0). If the given handle isn’t a handle to a resource, WriteResource does nothing, and ResError returns the result code resNotFound.

DISCUSSION

Note that this function does not write the resource’s resource map entry to disk.

When your application calls ChangedResource or AddResource, the Resource Manager attempts to reserve disk space for the changed resource. If the modified resource data can’t be written to the resource fork (for example, if there’s not enough room on disk), the resChanged attribute is not set to 1. If this is the case and you call WriteResource, the Resource Manager won’t know that the resource data has been changed. Thus, the function won’t write the modified resource data to the resource fork and won’t return an error. For this reason, always make sure that the ResError function returns the result code noErr after a call to ChangedResource or AddResource.

The resource fork is updated automatically when your application quits, when you call the UpdateResFile function, or when you call the CloseResFile function. Thus, you should call WriteResource only if you want to write just one or a few resources immediately.

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)