There is shockingly very little documentation on how to use uFFI. In
particular, I have the following situation...

A shared C lib has the following function:

void get_machine(char *machine) {
�� �� �� �� uname(&uname_s);
�� �� �� �� strcpy(machine, uname_s.machine);
}

It copies the content of a string value into the buffer passed to it (char
*machine).

I want to call this function from Pharo, thus:

buffer := String new: 64.
self ffiCall: #( void get_machine(String buffer) ).

The buffer never receives the string value (it just contains the 64
initiialized spaces).

Clearly, I'm misunderstanding the proper mechanism for doing this.

[There are other functions in the shared C lib that work fine, such as:

uint get_uptime() {
�� �� �� �� sysinfo(&info);
�� �� �� �� return info.uptime;
}

Returning integers or floats is no problem. But passing arguments by
reference seems to be verboten.]



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