#pragma C compiler directive

[Dean Grover]

While looking in /usr/include/vfork.h under SunOS 4.0.3, I noticed the
following line:
#pragma unknown_control_flow(vfork)

I can guess what that means to the C compiler, but my question is,
where is the #pragma compiler directive documented ?  I haven't been
able to find it anywhere.

Also, besides "unknown_control_flow", what other options exist ?

Thanks in advance,
Dean Grover
Hughes Aircraft Co.
grover at sed170.hac.com or adgrover at hac2arpa.hac.com