What does thread safe mean??

[Anandprasanna Gaitonde]

HI all,

I am eager to know  the meaning of  the macro
NS_IMPL_THREADSAFE_ISUPPORTS4(...)

What does it do and when should it be used.???

Actually i am using it and getting a Debug Assertion failure.in file
dbgheap.c  . I am working on WIN NT.

Please provide info on the macro.

Thanks ina advance

Regards
Prasanna