Add re-exec for server This allows ASLR to re-randomize the address space for every connection, preventing some vulnerabilities from being exploitable by repeated probing. Overhead (memory and time) is yet to be confirmed. At present this is only enabled on Linux. Other BSD platforms with fexecve() would probably also work though have not been tested.

#!/bin/sh

# Wrap all "#define X Y" with a #ifndef X...#endif"

sed 's/^\( *#define \([^ ][^ ]*\) .*\)/#ifndef \2\
\1\
#endif/'