Code:
#0 0x4207a6db in strlen () from /lib/tls/libc.so.6
(gdb) bt
#0 0x4207a6db in strlen () from /lib/tls/libc.so.6
#1 0x420477ed in vfprintf () from /lib/tls/libc.so.6
#2 0x420645fc in vsprintf () from /lib/tls/libc.so.6
#3 0x4001a500 in sprintf () from /lib/libsafe.so.2
#4 0x08077011 in Zone::SaveZoneCFG(char const*) (this=0x0,
filename=0x1 <Address 0x1 out of bounds>) at zone.cpp:536
This is for the #zsave command