install.pike: Update CXX smartlink path to installed path as well.
Stdio.File: More race fixes in connect() [bug 7293].

It seems the backend on Linux sometimes may trigger before the connect(2)
is done with POLLIN and a state where read(2) fails with ENOTCONN.

Reduce the race condition by inhibiting backend callbacks on the
fd during connect(2).
Silence release script warnings.
Fixed a few typos
Whitespace changes only
Do not test each and every file in ABI dirs

Once we know that the directory fulfills the search conditions, stop
running file on the files. Saves about 30 seconds on a full configure
run for me.
Removed MAX_FD configure test

It only returns the current max anyway, which is usually
smaller than the max if you are running as root, and can
also be changed at any time at runtime.

Instead, use sysconf(_SC_OPEN_MAX) when available if needed, and as a
last resort a hardcoded value (on Windows), but as a secondary change
all uses except two was removed:

o Stdio.get_all_active_fd - On systems without /dev/fd and
  /proc/self/fd.

o On NT, the size of FD_SET is now set to a hardcoded value (64k).

The rewrite of get_all_active_fd also speeds it up a lot. Not that it
is a frequently used function.
Whitespace changes
Optimized case for array += ({..}) when refs==2.

This was sort of done before, but it first assigned the lvalue
to 0, then assigned it back to the array once done.

This new version is about 2x faster, improving the "append array"
benchmark by about 60%.
Added a simple append_mapping instruction.

Much like append_array, but for mappings.  This speeds up the append
mapping benchmark by about (currently) 1000x.

However, that is somewhat misleading since the refs optimization is
not done currently since the wrong assignment operator ends up being
used.

Even when that is fixed the speedup should is still more than 2x,
however.
Stdio.Buffer now works on 32bit systems
io_rewind is already applied in io_call_write. Don't do it again in output_to.
Fixed output_to nbytes feature for non-file objects.
Don't corrupt send counter on error.
While any data can be sent, continue sending.
No need to limit data to write here.
Re-add early exit if not a full write was accepted. This is most often an optimazation.
Simplified debug a bit. data is always an array here.