People using the Windows operating system sometimes encounter such an error message: "0x00000000 memory referenced by the instruction "0X????????, the memory cannot be written", and then the application is closed. If you go to ask some "master", the answer is often "Windows is such unstable" and such disappointment. In fact, this error is not necessarily caused by Windows instability. This article is a simple analysis of the common causes of this error.
First, the application does not check the memory allocation failure
When the program needs a piece of memory to save the data, you need to call the operating system to provide the "function function" to apply, if the memory allocation is successful, the function will The newly opened memory area address is returned to the application, and the application can use this memory through this address. This is "dynamic memory allocation", the memory address is also the "pointer" in programming.
Memory is not always coming in, it is inexhaustible, and sometimes memory allocation will fail. When the allocation fails, the system function returns a value of 0. At this time, the return value “0” does not indicate the newly enabled pointer, but a notification sent by the system to the application to inform that an error has occurred. As an application, you should check whether the return value is 0 after applying for memory every time. If it is, it means that there is a failure, and some measures should be taken to save it, which enhances the program's "robustness".
If the application does not check for this error, it will follow the "inertia" thinking that this value is the available pointer to it and continue to use it in subsequent runs. The real 0 address memory area holds the most important "interrupt descriptor table" in the computer system, and the application is never allowed to be used. In an operating system without a protection mechanism (such as DOS), writing data to this address will cause an immediate crash. In a robust operating system, such as Windows, this operation will be immediately captured by the system's protection mechanism. The result is The operating system forcibly shuts down the wrong application to prevent its error from expanding. At this time, the above "write memory" error will occur, and the referenced memory address is "0x00000000".
There are many reasons for memory allocation failures, memory shortage, system function version mismatch, etc. may have an impact. Therefore, this allocation failure is more common after the operating system has been used for a long time, after installing a variety of applications (including inadvertently "installed" virus program), after changing a large number of system parameters and system files.
Second, the application because of its own BUG reference to the abnormal memory pointer
In the use of dynamically allocated applications, sometimes there will be such a situation: the program tries to read and write a piece of "should be available" memory But I don't know why, this expected pointer is no longer valid. It may be that "forgot" " to the operating system to request the allocation, it may be that the program itself has written off the memory at some point and "not pay attention" & so on. The unregistered memory is reclaimed by the system, and its access right is no longer in the application. Therefore, the read and write operations will also trigger the system's protection mechanism. The only end of the program that attempts to “illegal” is to be terminated by the operation, and all the recovery is completed. Resources. The laws of the computer world are still much more effective and stricter than humans!
The situation like this is a bug of the program itself, and you can often reproduce the error in a specific order of operation. Invalid pointers are not always 0, so the memory address in the error prompt is not necessarily "ldx; 0x00000000", but other random numbers.
If the system often mentions the error, the following suggestions may be helpful:
(1) Check if there is a Trojan or virus in the system. Such programs often irresponsibly modify the system in order to control the system, resulting in an operating system exception. It is common to strengthen information security awareness and not be curious about executable programs of unknown origin.
(2) update the operating system, let the operating system installer re-copy the correct version of the system file, and modify the system parameters. Sometimes the operating system itself will have a bug, pay attention to the installation of the official release of the upgrade program.
(3) Try a new version of the app.