public boolean isExternalEntryPoint(Address toAddr) {
		if (!toAddr.isMemoryAddress()) {
			return false;
		}
		lock.acquire();
		try {
			RefList refList = getToRefs(toAddr);
			if (refList != null) {
				return refList.getRef(Address.EXT_FROM_ADDRESS, CodeUnit.MNEMONIC) != null;
			}
		}
		catch (IOException e) {
			program.dbError(e);
		}
		finally {
			lock.release();
		}
		return false;
	}
Return whether the address is an external entry point
@param toAddr the memory address to test for external entry point
@return true if the address is an external entry point
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/references/ReferenceDBManager.java