Since 7d353bbe, _GNU_SOURCE is always
defined, which implies __USE_MINGW_ANSI_STDIO and thus switches to
the mingw implementations of the printf() family.  That's
standards-compliant, unlike Microsoft's CRT implementations.

Since 7d353bbe, _GNU_SOURCE is always
defined, which implies __USE_MINGW_ANSI_STDIO and thus switches to
the mingw implementations of the printf() family.  That's
standards-compliant, unlike Microsoft's CRT implementations.

Only _WIN32 is defined by the compiler, and WIN32 is not standardized
and may be missing.

Closes #169

.. and not the stack buffer.  This made the AllocatedString destructor
crash.

Closes #52

On mingw32, snprintf() expects a 64 bit integer instead of a "long
int" for "%li" - this is not consistent with our expectation, so we're
using plain sprintf().

After we've been hit by Large File Support problems several times in
the past week (which only occur on 32 bit platforms, which I don't
have), this is yet another attempt to fix the issue.

The soure file client.c has nearly 1000 lines, time for splitting it
into smaller pieces to improve readability.