Increase the BUFSIZ-long buffers [v9.16]
The BUFSIZ value varies between platforms, it could be 8K on Linux and 512 bytes on mingw. Make sure the buffers are always big enough for the output data to prevent truncation of the output by appropriately enlarging or sizing the buffers.
(cherry picked from commit b19d9322)
Closes #3453 (closed)
Edited by Ondřej Surý