Compilation errors with gcc 3.0.4

[Richard Peters]

Hello,

I tried to compile ncurses 5.2 with gcc 3.0.4, but I got compilation errors on
c++/cursesw.cc, lines 55 and 77, stating that std::strstreambuf doesn't have a
member vscan. I double checked the c++ standard, and gcc seems to be right on 
this.
My guess is that from version 3, gcc removed the non-standard function vscan 
from
std::strstreambuf.
Would changing
    strstreambuf ss(buf, sizeof(buf));
    result = ss.vscan(fmt, (_IO_va_list)args);
into
    result = vsscanf(buf, fmt, args);
fix the problem correctly? After this change, ncurses compiles, but I can't
adequately test if the behaviour is the same.

Thanks,

Richard Peters