how to set up a breakpoint in windbg?

Im having a bug in AIR debug launcher and 开发者_JS百科I have been trying to investigate with windbg, but i dont know how to use it. Can someone tell me the syntaxe to add a breakpoint to this bugging function (whatever the address can be...). I would like to put the breakpoint when i load the exe and i dont know at all how to set it so it will stop the debugger before crashing and i may be able to see what did call this function...

Let me thank you for any help.

I've found the command "bu ntdll32!RtlIntegerToUnicodeString" to work.