如何查询centos查看系统内核版本,系统版本,32位还是64位

查看centos内核的版本：
[root@localhost /]# cat /proc/version
Linux version 2.6.32-131.0.15.el6.x86_64 ([e-mail]) (gcc version 4.4.4 20100726 (Red Hat 4.4.4-13) (GCC) ) #1 SMP Sat Nov 12 15:11:58 CST 2011
[root@localhost /]#

[root@localhost /]# uname -a
Linux localhost.localdomain 2.6.32-131.0.15.el6.x86_64 #1 SMP Sat Nov 12 15:11:58 CST 2011 x86_64 x86_64 x86_64 GNU/Linux

查看linux版本：
[root@localhost /]# cat /etc/issue
CentOS release 6.1 (Final)
Kernel \r on an \m


[root@localhost /]# cat /etc/redhat-release
CentOS release 6.1 (Final)
[root@localhost /]#

查看系统是64位还是32位:
[root@localhost /]# getconf LONG_BIT
64
[root@localhost /]# getconf WORD_BIT
32
[root@localhost /]#

[root@localhost /]# file /bin/ls
/bin/ls: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.18, stripped
[root@localhost /]#