How to make gdb print out all values in hexadecimal mode?

[root@gdc1000 routing]# gdb
Traceback (most recent call last):
  File "<string>", line 35, in <module>
  File "/usr/local/share/gdb/python/gdb/__init__.py", line 19, in <module>
    import _gdb
ImportError: No module named _gdb
GNU gdb (GDB) Red Hat Enterprise Linux (7.2-75.el6)
Copyright (C) 2010 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-redhat-linux-gnu".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
(gdb) set output 16
Output radix now set to decimal 16, hex 10, octal 20.
(gdb) 

set output 16