Standard Input/Output and I/O Redirection

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[root@server1 ~]# who > users
[root@server1 ~]# cat users
root     pts/1        2011-04-12 17:29 (192.168.1.2)
root     pts/2        2011-04-12 18:20 (192.168.1.2)

[root@server1 ~]# wc -l < users
2

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