public static File getFile(String parent, String filename) {
		File file = findFile(parent, filename);
		if (file != null) {
			return file;
		}
		// filename lower
		file = findFile(parent, filename.toLowerCase());
		if (file != null) {
			return file;
		}
		// parent and filename lower
		file = findFile(parent.toLowerCase(), filename.toLowerCase());
		if (file != null) {
			return file;
		}
		// parent and filename upper
		file = findFile(parent.toUpperCase(), filename.toUpperCase());
		return file;
	}
Given a throwable, attempt pull out the significant error parts to generate a 
user-friendly error message.

@param t the throwable to examine, originating from the {@link CParser}.
@param functionString the full function signature text that was parsed by the parser.
@return a user-friendly error message, or null if this class did not know how to 
        handle the given exception.
Ghidra/Features/Base/src/main/java/ghidra/app/util/cparser/C/CParserUtils.java