Prints a description of a Core Foundation object to stderr.
- iOS 2.0+
- macOS 10.0+
- UIKit for Mac 13.0+Beta
- tvOS 9.0+
- watchOS 2.0+
- Core Foundation
A Core Foundation object derived from CFType. If
objis not a Core Foundation object, an assertion is raised.
The output is printed to the standard I/O standard error (stderr).
This function is useful as a debugging aid for Core Foundation objects. Because these objects are based on opaque types, it is difficult to examine their contents directly. However, the opaque types implement
description function callbacks that return descriptions of their objects. This function invokes these callbacks.
You can use
CFShow in one of two general ways. If your debugger supports function calls (such as
gdb does), call
CFShow in the debugger:
You can also incorporate calls to
CFShow in a test version of your code to print out "snapshots" of Core Foundation objects to the console.