threads question

[Michael C. Shultz]

Hi, I've just reached a point in a program I'm writing where I'd like to 
do threading.

When I try to start a thread like this:

pthread_create(&thread, &attr, MGPMrUpgrade, property );

where property is a structure of many variables it doesn't get passed
to the function.  If I do this:

pthread_create(&thread, &attr, MGPMrUpgrade( &property ), NULL );

It works, but just seems wrong.

Can anyone point me to a source file, preferably in /usr/src somewhere
that passes a structure to a function being run as a thread so I may 
study the proper way to do this?

Thank you.

-Mike