7.Shell
2.uniq - report or omit repeated lines
(1)語法
[dmtsai@study ~]$ uniq [-ic]
選項與參數:
-i:忽略大小寫字符的不同;
-c :進行計數
(2)用法
[root@localhost tmp]# last|cut -d " " -f 1 >last
[root@localhost tmp]# cat last
root
root
(unknown
reboot
root
root
root
(unknown
root
root
root
(unknown
root
root
root
(unknown
reboot
root
root
root
root
(unknown
reboot
wtmp
[root@localhost tmp]# uniq last
root #不帶任何參數,去掉連續重複的行
(unknown
reboot
root
(unknown
root
(unknown
root
(unknown
reboot
root
(unknown
reboot
wtmp
[root@localhost tmp]# uniq -c last
2 root #統計重複的次數
1 (unknown
1 reboot
3 root
1 (unknown
3 root
1 (unknown
3 root
1 (unknown
1 reboot
4 root
1 (unknown
1 reboot
1
1 wtmp
[root@localhost tmp]# uniq -d last
root #只顯示重複的行
root
root
root
root
[root@localhost tmp]# uniq -u last
(unknown #只顯示不重複的行
reboot
(unknown
(unknown
(unknown
reboot
(unknown
reboot
wtmp
[root@localhost tmp]# sort last |uniq -c
1 #排序後統計重複的行
3 reboot
15 root
5 (unknown
1 wtmp
#uniq 不會檢查重複的行,除非它們是相鄰的行。
3.wc - print newline, word, and byte counts for each file
(1)語法
[dmtsai@study ~]$ wc [-lwm]
選項與參數:
-l :僅列出行;
-w :僅列出多少字(英文單字);
-m :多少字符;
(2)用法
[root@localhost tmp]# cat wc.file
google 110 5140
baidu 100 532
guge 50 3900
sohu 100 4500
[root@localhost tmp]# wc wc.file
4 12 57 wc.file #統計行、單詞和字節數
[root@localhost tmp]# wc -l wc.file
4 wc.file # 統計行數
[root@localhost tmp]# wc -c wc.file
57 wc.file #統計字節數
[root@localhost tmp]# wc -w wc.file
12 wc.file #統計單詞數
[root@localhost tmp]# wc -m wc.file
57 wc.file #統計字符數