Typically for local variables I initialize them as late as I can. It's rare that I need a "dummy" value. However, if you do, you can use any value you like - it won't make any difference, if you're sure you're going to assign a value before reading it.
If you want the char
equivalent of 0, it's just Unicode 0, which can be written as
char c = '\0';
That's also the default value for an instance (or static) variable of type char
.