What is a binary null character?

Question

I have a requirement to create a sysDesk log file. In this requirement I am supposed to create an XML file, that in certain places between the elements contains a binary null character. Can someone please explain to me, firstly what is a binary null character, and how can I write one to a text file?

Accepted Answer

I suspect it means Unicode U+0000. However, that's not a valid character in an XML file... you should see if you can get a very clear specification of the file format to work out what's actually required. Sample files would also be useful :)

Comments are failing me at the moment, so to address a couple of other answers:

It's not a string termination character in C#, as C# doesn't use null-terminated strings. In fact, all .NET strings are null-terminated for the sake of interop, but more importantly the length is stored independently. In particular, a C# string can entirely validly include a null character without terminating it:

```
string embeddedNull = "a\0b";
Console.WriteLine(embeddedNull.Length); // Prints 3
```

The method given by rwmnau for getting a null character or string is very inefficient for something simple. Better would be:

```
string justNullString = "\0";
char justNullChar = '\0';
```

What is a binary null character?

Solution

Problem