Regarding https://bitcointalk.org/index.php?topic=28022.0
main.cpp has: "char pchMessageStart[4] = { 0xf9, 0xbe, 0xb4, 0xd9 };"
Per discussion on the thread linked, leaving the signedness of
pchMessageStart is unsafe for values > 0x80. This patch specifies
'unsigned char' in main.cpp and net.h.
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
Introduce SendBufferSize() and ReceiveBufferSize(), and limit
the blocks sent as response to the "getblocks" message to
half of the active send buffer size.
Use non-blocking connects, and a select() call to wait a predefined
time (5s by default, but configurable with -timeout) for either
success or failure. This allows much more connections to be tried
per time unit.
Based on a patch by phantomcircuit.
Venkatesh Srinivas