gdb输出信息过长，需要取前面的数据，下面这种方法好
(gdb) set logging file <file name>
(gdb) set logging on
(gdb) info functions
(gdb) set logging off
完了就可以去取数据了
Num Basename Type Address Reason | | Source
| | | | | | | |
1 OpenDoor - 0x74000 exec C C /private/var/mobile/Applications/4D1038EB-EE94-41A1-A9FE-405D77510CBF/OpenDoor.app/OpenDoor at 0x74000 (offset 0x73000)
(objfile is) [memory object "/private/var/mobile/Applications/4D1038EB-EE94-41A1-A9FE-405D77510CBF/OpenDoor.app/OpenDoor" at 0x74000]
参考:
http://blog.csdn.net/ariesjzj/article/details/7419479