9.6-9.7 awk
扩展
把这里面的所有练习题做一下
http://www.apelearn.com/study_v2/chapter14.html
# 9.6 awk 上
- 同样的 创建一个目录awk，把/etc/passwd 文件拷贝到 目录awk下，改名为test.txt
```
[[email protected] ~]# mkdir awk
[[email protected] ~]# cp /etc/passwd awk/test.txt
[[email protected] ~]# cd awk
[[email protected] awk]# ls
test.txt
```
- 匹配test.txt 文件第一列 用冒号分隔符分开 awk -F ‘:‘ ‘{print $1}‘ test.txt
```
[[email protected] awk]# awk -F ‘:‘ ‘{print $1}‘ test.txt
root
bin
daemon
adm
lp
sync
shutdown
halt
mail
operator
games
ftp
nobody
systemd-bus-proxy
systemd-network
dbus
polkitd
tss
postfix
sshd
chrony
aming
user1
user2
user3
user4
user5
user6
saslauth
[[email protected] awk]#
```
- 打印所有的段 awk -F ‘:‘ ‘{print $0}‘ test.txt 所有的段用 $0 表示， 第一段用$1
```
[[email protected] awk]# awk -F ‘:‘ ‘{print $0}‘ test.txt
root:x:0:0:root:/root:/bin/bash
bin:x:1:1:bin:/bin:/sbin/nologin
daemon:x:2:2:daemon:/sbin:/sbin/nologin
adm:x:3:4:adm:/var/adm:/sbin/nologin
lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
sync:x:5:0:sync:/sbin:/bin/sync
shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
halt:x:7:0:halt:/sbin:/sbin/halt
mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
operator:x:11:0:operator:/root:/sbin/nologin
games:x:12:100:games:/usr/games:/sbin/nologin
ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin
nobody:x:99:99:Nobody:/:/sbin/nologin
systemd-bus-proxy:x:999:997:systemd Bus Proxy:/:/sbin/nologin
systemd-network:x:192:192:systemd Network Management:/:/sbin/nologin
dbus:x:81:81:System message bus:/:/sbin/nologin
polkitd:x:998:996:User for polkitd:/:/sbin/nologin
tss:x:59:59:Account used by the trousers package to sandbox the tcsd daemon:/dev/null:/sbin/nologin
postfix:x:89:89::/var/spool/postfix:/sbin/nologin
sshd:x:74:74:Privilege-separated SSH:/var/empty/sshd:/sbin/nologin
chrony:x:997:995::/var/lib/chrony:/sbin/nologin
aming:x:1000:1005::/home/aming:/bin/bash
user1:x:1001:1001::/home/user1:/bin/bash
user2:x:1002:1002::/home/user2:/bin/bash
user3:x:1004:1005::/home/user3:/bin/bash
user4:x:1006:1005::/home/aming111:/sbin/nologin
user5:x:1007:1007::/home/user5:/bin/bash
user6:x:1008:1010::/home/user6:/bin/bash
saslauth:x:996:76:Saslauthd user:/run/saslauthd:/sbin/nologin
[[email protected] awk]#
```
- awk ‘{print $0}‘ test.txt 这个功能 有点像cat的
- awk 没有指定分隔符，默认会以空格，空白字符作为分隔符去打印
```
[[email protected] awk]# awk ‘{print $0}‘ test.txt
root:x:0:0:root:/root:/bin/bash
bin:x:1:1:bin:/bin:/sbin/nologin
daemon:x:2:2:daemon:/sbin:/sbin/nologin
adm:x:3:4:adm:/var/adm:/sbin/nologin
lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
sync:x:5:0:sync:/sbin:/bin/sync
shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
halt:x:7:0:halt:/sbin:/sbin/halt
mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
operator:x:11:0:operator:/root:/sbin/nologin
games:x:12:100:games:/usr/games:/sbin/nologin
ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin
nobody:x:99:99:Nobody:/:/sbin/nologin
systemd-bus-proxy:x:999:997:systemd Bus Proxy:/:/sbin/nologin
systemd-network:x:192:192:systemd Network Management:/:/sbin/nologin
dbus:x:81:81:System message bus:/:/sbin/nologin
polkitd:x:998:996:User for polkitd:/:/sbin/nologin
tss:x:59:59:Account used by the trousers package to sandbox the tcsd daemon:/dev/null:/sbin/nologin
postfix:x:89:89::/var/spool/postfix:/sbin/nologin
sshd:x:74:74:Privilege-separated SSH:/var/empty/sshd:/sbin/nologin
chrony:x:997:995::/var/lib/chrony:/sbin/nologin
aming:x:1000:1005::/home/aming:/bin/bash
user1:x:1001:1001::/home/user1:/bin/bash
user2:x:1002:1002::/home/user2:/bin/bash
user3:x:1004:1005::/home/user3:/bin/bash
user4:x:1006:1005::/home/aming111:/sbin/nologin
user5:x:1007:1007::/home/user5:/bin/bash
user6:x:1008:1010::/home/user6:/bin/bash
saslauth:x:996:76:Saslauthd user:/run/saslauthd:/sbin/nologin
[[email protected] awk]#
```
---
- 来创建一个测试的文件 1.txt, awk ‘{print $1}‘ 1.txt 不指定分隔符，就以空格 空白字符作位分隔符
```
[[email protected] awk]# vim 1.txt
1 2
aa bb
dd ee
[[email protected] awk]# awk ‘{print $1}‘ 1.txt
1
aa
dd
[[email protected] awk]# cat 1.txt
1 2
aa bb
dd ee
```
-想要多看几段内容,中间用逗号隔开，awk -F ‘:‘ ‘{print $1,$3,$4}‘ test.txt
```
[[email protected] awk]# awk -F ‘:‘ ‘{print $1,$3,$4}‘ test.txt
root 0 0
bin 1 1
daemon 2 2
adm 3 4
lp 4 7
sync 5 0
shutdown 6 0
halt 7 0
mail 8 12
operator 11 0
games 12 100
ftp 14 50
nobody 99 99
systemd-bus-proxy 999 997
systemd-network 192 192
dbus 81 81
polkitd 998 996
tss 59 59
postfix 89 89
sshd 74 74
chrony 997 995
aming 1000 1005
user1 1001 1001
user2 1002 1002
user3 1004 1005
user4 1006 1005
user5 1007 1007
user6 1008 1010
saslauth 996 76
[[email protected] awk]#
```
- 也可以指定中间以什么符号分割，比如用#号分割 awk -F ‘:‘ ‘{print $1"#"$3"#"$4}‘ test.txt
```
[[email protected] awk]# awk -F ‘:‘ ‘{print $1"#"$3"#"$4}‘ test.txt
root#0#0
bin#1#1
daemon#2#2
adm#3#4
lp#4#7
sync#5#0
shutdown#6#0
halt#7#0
mail#8#12
operator#11#0
games#12#100
ftp#14#50
nobody#99#99
systemd-bus-proxy#999#997
systemd-network#192#192
dbus#81#81
polkitd#998#996
tss#59#59
postfix#89#89
sshd#74#74
chrony#997#995
aming#1000#1005
user1#1001#1001
user2#1002#1002
user3#1004#1005
user4#1006#1005
user5#1007#1007
user6#1008#1010
saslauth#996#76
[[email protected] awk]#
```
- [ ] awk匹配功能
- awk 把包含oo的行打印出来
```
[[email protected] awk]# awk ‘/oo/‘ test.txt
root:x:0:0:root:/root:/bin/bash
lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
operator:x:11:0:operator:/root:/sbin/nologin
postfix:x:89:89::/var/spool/postfix:/sbin/nologin
[[email protected] awk]#
```
-匹配test.txt文件 第1段 包含oo的行
```
[[email protected] awk]# awk -F ‘:‘ ‘$1 ~ /oo/‘ test.txt
root:x:0:0:root:/root:/bin/bash
[[email protected] awk]#
```
- awk 匹配也支持 正则表达式 awk -F ‘:‘ ‘$1 ~ /o+/‘ test.txt
```
[[email protected] awk]# awk -F ‘:‘ ‘$1 ~ /o+/‘ test.txt
root:x:0:0:root:/root:/bin/bash
daemon:x:2:2:daemon:/sbin:/sbin/nologin
shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
operator:x:11:0:operator:/root:/sbin/nologin
nobody:x:99:99:Nobody:/:/sbin/nologin
systemd-bus-proxy:x:999:997:systemd Bus Proxy:/:/sbin/nologin
systemd-network:x:192:192:systemd Network Management:/:/sbin/nologin
polkitd:x:998:996:User for polkitd:/:/sbin/nologin
postfix:x:89:89::/var/spool/postfix:/sbin/nologin
chrony:x:997:995::/var/lib/chrony:/sbin/nologin
[[email protected] awk]# awk -F ‘:‘ ‘$1 ~ /oo+/‘ test.txt
root:x:0:0:root:/root:/bin/bash
[[email protected] awk]#
```
- awk 支持多个表达式 awk -F ‘:‘ ‘/root/ {print $1,$3} /user/ {print $3,$4}‘ test.txt
```
[[email protected] awk]# awk -F ‘:‘ ‘/root/ {print $1,$3} /user/ {print $3,$4}‘ test.txt
root 0
operator 11
59 59
1001 1001
1002 1002
1004 1005
1006 1005
1007 1007
1008 1010
996 76
[[email protected] awk]# grep -E ‘root|user‘ test.txt
root:x:0:0:root:/root:/bin/bash
operator:x:11:0:operator:/root:/sbin/nologin
tss:x:59:59:Account used by the trousers package to sandbox the tcsd daemon:/dev/null:/sbin/nologin
user1:x:1001:1001::/home/user1:/bin/bash
user2:x:1002:1002::/home/user2:/bin/bash
user3:x:1004:1005::/home/user3:/bin/bash
user4:x:1006:1005::/home/aming111:/sbin/nologin
user5:x:1007:1007::/home/user5:/bin/bash
user6:x:1008:1010::/home/user6:/bin/bash
saslauth:x:996:76:Saslauthd user:/run/saslauthd:/sbin/nologin
[[email protected] awk]#
```
- 包含root 或者包含user的 全部打印出来
```
[[email protected] awk]# awk -F ‘:‘ ‘/root|user/ {print $0}‘ test.txt
root:x:0:0:root:/root:/bin/bash
operator:x:11:0:operator:/root:/sbin/nologin
tss:x:59:59:Account used by the trousers package to sandbox the tcsd daemon:/dev/null:/sbin/nologin
user1:x:1001:1001::/home/user1:/bin/bash
user2:x:1002:1002::/home/user2:/bin/bash
user3:x:1004:1005::/home/user3:/bin/bash
user4:x:1006:1005::/home/aming111:/sbin/nologin
user5:x:1007:1007::/home/user5:/bin/bash
user6:x:1008:1010::/home/user6:/bin/bash
saslauth:x:996:76:Saslauthd user:/run/saslauthd:/sbin/nologin
[[email protected] awk]#
```
- 针对数学 运算表达式的,这里的 第三段等于0 必须$3==0 俩个等于号，如果是一个 就成了shell变量了
```
[[email protected] awk]# awk -F ‘:‘ ‘$3==0‘ test.txt
root:x:0:0:root:/root:/bin/bash
[[email protected] awk]# awk -F ‘:‘ ‘$3==0 {print $1}‘ test.txt
root
[[email protected] awk]#
```
-匹配第三段数字大于等于 1000的数字 打印第一行
```
[[email protected] awk]# awk -F ‘:‘ ‘$3>=1000 {print $1}‘ test.txt
aming
user1
user2
user3
user4
user5
user6
```
-匹配第三段大于等于1000的数字 并且打印全部行
```
[[email protected] awk]# awk -F ‘:‘ ‘$3>=1000 {print $0}‘ test.txt
aming:x:1000:1005::/home/aming:/bin/bash
user1:x:1001:1001::/home/user1:/bin/bash
user2:x:1002:1002::/home/user2:/bin/bash
user3:x:1004:1005::/home/user3:/bin/bash
user4:x:1006:1005::/home/aming111:/sbin/nologin
user5:x:1007:1007::/home/user5:/bin/bash
user6:x:1008:1010::/home/user6:/bin/bash
[[email protected] awk]#
```
- 注意数字加""双引号 和不加双引号的区别 加双引号会认为是一个字符串，以阿斯玛的排序方式计算的 如果是数字 不要加双引号
```
[[email protected] awk]# awk -F ‘:‘ ‘$3>="1000" {print $0}‘ test.txt
daemon:x:2:2:daemon:/sbin:/sbin/nologin
adm:x:3:4:adm:/var/adm:/sbin/nologin
lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
sync:x:5:0:sync:/sbin:/bin/sync
shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
halt:x:7:0:halt:/sbin:/sbin/halt
mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
operator:x:11:0:operator:/root:/sbin/nologin
games:x:12:100:games:/usr/games:/sbin/nologin
ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin
nobody:x:99:99:Nobody:/:/sbin/nologin
systemd-bus-proxy:x:999:997:systemd Bus Proxy:/:/sbin/nologin
systemd-network:x:192:192:systemd Network Management:/:/sbin/nologin
dbus:x:81:81:System message bus:/:/sbin/nologin
polkitd:x:998:996:User for polkitd:/:/sbin/nologin
tss:x:59:59:Account used by the trousers package to sandbox the tcsd daemon:/dev/null:/sbin/nologin
postfix:x:89:89::/var/spool/postfix:/sbin/nologin
sshd:x:74:74:Privilege-separated SSH:/var/empty/sshd:/sbin/nologin
chrony:x:997:995::/var/lib/chrony:/sbin/nologin
aming:x:1000:1005::/home/aming:/bin/bash
user1:x:1001:1001::/home/user1:/bin/bash
user2:x:1002:1002::/home/user2:/bin/bash
user3:x:1004:1005::/home/user3:/bin/bash
user4:x:1006:1005::/home/aming111:/sbin/nologin
user5:x:1007:1007::/home/user5:/bin/bash
user6:x:1008:1010::/home/user6:/bin/bash
saslauth:x:996:76:Saslauthd user:/run/saslauthd:/sbin/nologin
[[email protected] awk]#
```
- 第7段不等于 不等于用!=表示,如果是字符串，加上""双引号，"/sbin/login"
```
[[email protected] awk]# awk -F ‘:‘ ‘$7!="/sbin/nologin" {print $0}‘ test.txt
root:x:0:0:root:/root:/bin/bash
sync:x:5:0:sync:/sbin:/bin/sync
shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
halt:x:7:0:halt:/sbin:/sbin/halt
aming:x:1000:1005::/home/aming:/bin/bash
user1:x:1001:1001::/home/user1:/bin/bash
user2:x:1002:1002::/home/user2:/bin/bash
user3:x:1004:1005::/home/user3:/bin/bash
user5:x:1007:1007::/home/user5:/bin/bash
user6:x:1008:1010::/home/user6:/bin/bash
[[email protected] awk]#
```
# 9.7 awk下
- 匹配 第三段数字小于第四段 awk -F ‘:‘ ‘$3<$4‘ test.txt
```
[[email protected] awk]# awk -F ‘:‘ ‘$3<$4‘ test.txt
adm:x:3:4:adm:/var/adm:/sbin/nologin
lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
games:x:12:100:games:/usr/games:/sbin/nologin
ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin
aming:x:1000:1005::/home/aming:/bin/bash
user3:x:1004:1005::/home/user3:/bin/bash
user6:x:1008:1010::/home/user6:/bin/bash
[[email protected] awk]#
```
-匹配 第三段等于第四段数字的
```
[[email protected] awk]# awk -F ‘:‘ ‘$3==$4‘ test.txt
root:x:0:0:root:/root:/bin/bash
bin:x:1:1:bin:/bin:/sbin/nologin
daemon:x:2:2:daemon:/sbin:/sbin/nologin
nobody:x:99:99:Nobody:/:/sbin/nologin
systemd-network:x:192:192:systemd Network Management:/:/sbin/nologin
dbus:x:81:81:System message bus:/:/sbin/nologin
tss:x:59:59:Account used by the trousers package to sandbox the tcsd daemon:/dev/null:/sbin/nologin
postfix:x:89:89::/var/spool/postfix:/sbin/nologin
sshd:x:74:74:Privilege-separated SSH:/var/empty/sshd:/sbin/nologin
user1:x:1001:1001::/home/user1:/bin/bash
user2:x:1002:1002::/home/user2:/bin/bash
user5:x:1007:1007::/home/user5:/bin/bash
[[email protected] awk]#
```
- 匹配 第三段大于5小于7 awk -F ‘:‘ ‘$3>"5" && $3<"7"‘ test.txt
```
[[email protected] awk]# awk -F ‘:‘ ‘$3>"5" && $3<"7"‘ test.txt
shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
tss:x:59:59:Account used by the trousers package to sandbox the tcsd daemon:/dev/null:/sbin/nologin
[[email protected] awk]#
```
- 匹配第三段大于数字1000 或者 第七段等于 /sbin/nologin
- awk -F ‘:‘ ‘$3>1000 || $7=="/sbin/nologin"‘ test.txt
```
[[email protected] awk]# awk -F ‘:‘ ‘$3>1000 || $7=="/sbin/nologin"‘ test.txt
bin:x:1:1:bin:/bin:/sbin/nologin
daemon:x:2:2:daemon:/sbin:/sbin/nologin
adm:x:3:4:adm:/var/adm:/sbin/nologin
lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
operator:x:11:0:operator:/root:/sbin/nologin
games:x:12:100:games:/usr/games:/sbin/nologin
ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin
nobody:x:99:99:Nobody:/:/sbin/nologin
systemd-bus-proxy:x:999:997:systemd Bus Proxy:/:/sbin/nologin
systemd-network:x:192:192:systemd Network Management:/:/sbin/nologin
dbus:x:81:81:System message bus:/:/sbin/nologin
polkitd:x:998:996:User for polkitd:/:/sbin/nologin
tss:x:59:59:Account used by the trousers package to sandbox the tcsd daemon:/dev/null:/sbin/nologin
postfix:x:89:89::/var/spool/postfix:/sbin/nologin
sshd:x:74:74:Privilege-separated SSH:/var/empty/sshd:/sbin/nologin
chrony:x:997:995::/var/lib/chrony:/sbin/nologin
user1:x:1001:1001::/home/user1:/bin/bash
user2:x:1002:1002::/home/user2:/bin/bash
user3:x:1004:1005::/home/user3:/bin/bash
user4:x:1006:1005::/home/aming111:/sbin/nologin
user5:x:1007:1007::/home/user5:/bin/bash
user6:x:1008:1010::/home/user6:/bin/bash
saslauth:x:996:76:Saslauthd user:/run/saslauthd:/sbin/nologin
[[email protected] awk]#
```
- 第三段大于1000 ，或者 第7段 带有/bash/ 的
- awk -F ‘:‘ ‘$3>1000 || $7 ~ /bash/‘ test.txt
```
[[email protected] awk]# awk -F ‘:‘ ‘$3>1000 || $7 ~ /bash/‘ test.txt
root:x:0:0:root:/root:/bin/bash
aming:x:1000:1005::/home/aming:/bin/bash
user1:x:1001:1001::/home/user1:/bin/bash
user2:x:1002:1002::/home/user2:/bin/bash
user3:x:1004:1005::/home/user3:/bin/bash
user4:x:1006:1005::/home/aming111:/sbin/nologin
user5:x:1007:1007::/home/user5:/bin/bash
user6:x:1008:1010::/home/user6:/bin/bash
[[email protected] awk]#
```
- 变量OFS="#" 用来指定print 分隔符用#隔开，打印第1，第3，第7段
- awk -F ‘:‘ ‘{OFS="#"} $3>1000 || $7 ~ /bash/ {print $1,$3,$7}‘ test.txt
```
[[email protected] awk]# awk -F ‘:‘ ‘{OFS="#"} $3>1000 || $7 ~ /bash/ {print $1,$3,$7}‘ test.txt
root#0#/bin/bash
aming#1000#/bin/bash
user1#1001#/bin/bash
user2#1002#/bin/bash
user3#1004#/bin/bash
user4#1006#/sbin/nologin
user5#1007#/bin/bash
user6#1008#/bin/bash
[[email protected] awk]#
```
- 不写条件,就是全部都用 # 号分隔符隔开 打印第1,3,7段 awk -F ‘:‘ ‘{OFS="#"} {print $1,$3,$7}‘ test.txt
```
[[email protected] awk]# awk -F ‘:‘ ‘{OFS="#"} {print $1,$3,$7}‘ test.txt
root#0#/bin/bash
bin#1#/sbin/nologin
daemon#2#/sbin/nologin
adm#3#/sbin/nologin
lp#4#/sbin/nologin
sync#5#/bin/sync
shutdown#6#/sbin/shutdown
halt#7#/sbin/halt
mail#8#/sbin/nologin
operator#11#/sbin/nologin
games#12#/sbin/nologin
ftp#14#/sbin/nologin
nobody#99#/sbin/nologin
systemd-bus-proxy#999#/sbin/nologin
systemd-network#192#/sbin/nologin
dbus#81#/sbin/nologin
polkitd#998#/sbin/nologin
tss#59#/sbin/nologin
postfix#89#/sbin/nologin
sshd#74#/sbin/nologin
chrony#997#/sbin/nologin
aming#1000#/bin/bash
user1#1001#/bin/bash
user2#1002#/bin/bash
user3#1004#/bin/bash
user4#1006#/sbin/nologin
user5#1007#/bin/bash
user6#1008#/bin/bash
saslauth#996#/sbin/nologin
[[email protected] awk]#
```
-匹配 第3段大于1000 ，并且用#作为后面打印1 2 3 4 段的分隔符
```
[[email protected] awk]# awk -F ‘:‘ ‘{OFS="#"} {if ($3>1000 ) {print $1,$2,$3,$4}}‘ test.txt
user1#x#1001#1001
user2#x#1002#1002
user3#x#1004#1005
user4#x#1006#1005
user5#x#1007#1007
user6#x#1008#1010
[[email protected] awk]#
或者
[[email protected] awk]# awk -F ‘:‘ ‘{OFS="#"} $3>1000 {print $1,$2,$3,$4}‘ test.txt
user1#x#1001#1001
user2#x#1002#1002
user3#x#1004#1005
user4#x#1006#1005
user5#x#1007#1007
user6#x#1008#1010
[[email protected] awk]#
```
- 打印所有的行，把所有的行打印出来 awk -F ‘:‘ ‘{print NR":"$0}‘ test.txt
```
[[email protected] awk]# awk -F ‘:‘ ‘{print NR":"$0}‘ test.txt
1:root:x:0:0:root:/root:/bin/bash
2:bin:x:1:1:bin:/bin:/sbin/nologin
3:daemon:x:2:2:daemon:/sbin:/sbin/nologin
4:adm:x:3:4:adm:/var/adm:/sbin/nologin
5:lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
6:sync:x:5:0:sync:/sbin:/bin/sync
7:shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
8:halt:x:7:0:halt:/sbin:/sbin/halt
9:mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
10:operator:x:11:0:operator:/root:/sbin/nologin
11:games:x:12:100:games:/usr/games:/sbin/nologin
12:ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin
13:nobody:x:99:99:Nobody:/:/sbin/nologin
14:systemd-bus-proxy:x:999:997:systemd Bus Proxy:/:/sbin/nologin
15:systemd-network:x:192:192:systemd Network Management:/:/sbin/nologin
16:dbus:x:81:81:System message bus:/:/sbin/nologin
17:polkitd:x:998:996:User for polkitd:/:/sbin/nologin
18:tss:x:59:59:Account used by the trousers package to sandbox the tcsd daemon:/dev/null:/sbin/nologin
19:postfix:x:89:89::/var/spool/postfix:/sbin/nologin
20:sshd:x:74:74:Privilege-separated SSH:/var/empty/sshd:/sbin/nologin
21:chrony:x:997:995::/var/lib/chrony:/sbin/nologin
22:aming:x:1000:1005::/home/aming:/bin/bash
23:user1:x:1001:1001::/home/user1:/bin/bash
24:user2:x:1002:1002::/home/user2:/bin/bash
25:user3:x:1004:1005::/home/user3:/bin/bash
26:user4:x:1006:1005::/home/aming111:/sbin/nologin
27:user5:x:1007:1007::/home/user5:/bin/bash
28:user6:x:1008:1010::/home/user6:/bin/bash
29:saslauth:x:996:76:Saslauthd user:/run/saslauthd:/sbin/nologin
[[email protected] awk]#
```
- 把所有的段打印出来 awk -F ‘:‘ ‘{print NF":"$0}‘ test.txt
```
[[email protected] awk]# awk -F ‘:‘ ‘{print NF":"$0}‘ test.txt
7:root:x:0:0:root:/root:/bin/bash
7:bin:x:1:1:bin:/bin:/sbin/nologin
7:daemon:x:2:2:daemon:/sbin:/sbin/nologin
7:adm:x:3:4:adm:/var/adm:/sbin/nologin
7:lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
7:sync:x:5:0:sync:/sbin:/bin/sync
7:shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
7:halt:x:7:0:halt:/sbin:/sbin/halt
7:mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
7:operator:x:11:0:operator:/root:/sbin/nologin
7:games:x:12:100:games:/usr/games:/sbin/nologin
7:ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin
7:nobody:x:99:99:Nobody:/:/sbin/nologin
7:systemd-bus-proxy:x:999:997:systemd Bus Proxy:/:/sbin/nologin
7:systemd-network:x:192:192:systemd Network Management:/:/sbin/nologin
7:dbus:x:81:81:System message bus:/:/sbin/nologin
7:polkitd:x:998:996:User for polkitd:/:/sbin/nologin
7:tss:x:59:59:Account used by the trousers package to sandbox the tcsd daemon:/dev/null:/sbin/nologin
7:postfix:x:89:89::/var/spool/postfix:/sbin/nologin
7:sshd:x:74:74:Privilege-separated SSH:/var/empty/sshd:/sbin/nologin
7:chrony:x:997:995::/var/lib/chrony:/sbin/nologin
7:aming:x:1000:1005::/home/aming:/bin/bash
7:user1:x:1001:1001::/home/user1:/bin/bash
7:user2:x:1002:1002::/home/user2:/bin/bash
7:user3:x:1004:1005::/home/user3:/bin/bash
7:user4:x:1006:1005::/home/aming111:/sbin/nologin
7:user5:x:1007:1007::/home/user5:/bin/bash
7:user6:x:1008:1010::/home/user6:/bin/bash
7:saslauth:x:996:76:Saslauthd user:/run/saslauthd:/sbin/nologin
[[email protected] awk]#
```
- 把test.txt第一行改成6段 ,再来打印 所有的段
```
[[email protected] awk]# vim test.txt
rootx:0:0:root:/root:/bin/bash
[[email protected] awk]# awk -F ‘:‘ ‘{print NF":"$0}‘ test.txt
6:rootx:0:0:root:/root:/bin/bash 这里变成6段了
7:bin:x:1:1:bin:/bin:/sbin/nologin
7:daemon:x:2:2:daemon:/sbin:/sbin/nologin
7:adm:x:3:4:adm:/var/adm:/sbin/nologin
7:lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
7:sync:x:5:0:sync:/sbin:/bin/sync
7:shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
7:halt:x:7:0:halt:/sbin:/sbin/halt
7:mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
7:operator:x:11:0:operator:/root:/sbin/nologin
7:games:x:12:100:games:/usr/games:/sbin/nologin
7:ftp:x:14:50:FTP User:/var/ftp:/sbin/nologin
7:nobody:x:99:99:Nobody:/:/sbin/nologin
7:systemd-bus-proxy:x:999:997:systemd Bus Proxy:/:/sbin/nologin
7:systemd-network:x:192:192:systemd Network Management:/:/sbin/nologin
7:dbus:x:81:81:System message bus:/:/sbin/nologin
7:polkitd:x:998:996:User for polkitd:/:/sbin/nologin
7:tss:x:59:59:Account used by the trousers package to sandbox the tcsd daemon:/dev/null:/sbin/nologin
7:postfix:x:89:89::/var/spool/postfix:/sbin/nologin
7:sshd:x:74:74:Privilege-separated SSH:/var/empty/sshd:/sbin/nologin
7:chrony:x:997:995::/var/lib/chrony:/sbin/nologin
7:aming:x:1000:1005::/home/aming:/bin/bash
7:user1:x:1001:1001::/home/user1:/bin/bash
7:user2:x:1002:1002::/home/user2:/bin/bash
7:user3:x:1004:1005::/home/user3:/bin/bash
7:user4:x:1006:1005::/home/aming111:/sbin/nologin
7:user5:x:1007:1007::/home/user5:/bin/bash
7:user6:x:1008:1010::/home/user6:/bin/bash
7:saslauth:x:996:76:Saslauthd user:/run/saslauthd:/sbin/nologin
[[email protected] awk]#
```
- NR作为一个判断条件 NR <= 小于等于10 也就是前10行 awk -F ‘:‘ ‘NR<=10‘ test.txt
```
[[email protected] awk]# awk -F ‘:‘ ‘NR<=10‘ test.txt
rootx:0:0:root:/root:/bin/bash
bin:x:1:1:bin:/bin:/sbin/nologin
daemon:x:2:2:daemon:/sbin:/sbin/nologin
adm:x:3:4:adm:/var/adm:/sbin/nologin
lp:x:4:7:lp:/var/spool/lpd:/sbin/nologin
sync:x:5:0:sync:/sbin:/bin/sync
shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown
halt:x:7:0:halt:/sbin:/sbin/halt
mail:x:8:12:mail:/var/spool/mail:/sbin/nologin
operator:x:11:0:operator:/root:/sbin/nologin
[[email protected] awk]#
```
- 打印 前10行 并且第一段 带有root 或者 sync 的段
```
[[email protected] awk]# awk -F ‘:‘ ‘NR<=10 && $1 ~ /root|sync/‘ test.txt
rootx:0:0:root:/root:/bin/bash
sync:x:5:0:sync:/sbin:/bin/sync
[[email protected] awk]#
```
- 打印 前10行 并且 第一段 带有root 或者 sync 的段 第一段段只有6段的 只有第一行符合条件
```
[[email protected] awk]# awk -F ‘:‘ ‘NF==6 && $1 ~ /root|sync/‘ test.txt
rootx:0:0:root:/root:/bin/bash
[[email protected] awk]#
```
- 有时候有这样的需求
```
[[email protected] awk]# awk -F ‘:‘ ‘{print $NR":"$NF}‘ test.txt
rootx:/bin/bash $1:$7
x:/sbin/nologin $2:$7
2:/sbin/nologin
4:/sbin/nologin
lp:/sbin/nologin
/sbin:/bin/sync
/sbin/shutdown:/sbin/shutdown $7:$7
:/sbin/halt 因为只有7段，后面就是空的 :$7
:/sbin/nologin :$7
:/sbin/nologin :$7
:/sbin/nologin
:/sbin/nologin
:/sbin/nologin
:/sbin/nologin
:/sbin/nologin
:/sbin/nologin
:/sbin/nologin
:/sbin/nologin
:/sbin/nologin
:/sbin/nologin
:/sbin/nologin
:/bin/bash
:/bin/bash
:/bin/bash
:/bin/bash
:/sbin/nologin
:/bin/bash
:/bin/bash
:/sbin/nologin :$7
[[email protected] awk]#
```
- 对test.txt前三行 赋值 第一段为root 一个等于号 就是赋值 ，俩个才是等于（匹配）
```
[[email protected] awk]# head -n 3 test.txt |awk -F ‘:‘ ‘$1="root"‘
root 0 0 root /root /bin/bash
root x 1 1 bin /bin /sbin/nologin
root x 2 2 daemon /sbin /sbin/nologin
用vim 把 文件内容第一段 改回来了
[[email protected] awk]# vim test.txt
[[email protected] awk]# vim test.txt
root:x:0:0:root:/root:/bin/bash
bin:x:1:1:bin:/bin:/sbin/nologin
```
-这个== 才是等于 匹配的意思 一个= 是赋值
```
[[email protected] awk]# head -n 3 test.txt |awk -F ‘:‘ ‘$1=="root"‘
root:x:0:0:root:/root:/bin/bash
[[email protected] awk]#
```
-发现赋值之后 分隔符没了，再定义分隔符 用冒号 ：隔开
```
[[email protected] awk]# head -n 3 test.txt |awk -F ‘:‘ ‘{OFS=":"} $1="root"‘
root:x:0:0:root:/root:/bin/bash
root:x:1:1:bin:/bin:/sbin/nologin
root:x:2:2:daemon:/sbin:/sbin/nologin
[[email protected] awk]#
```
- 分段，然后是语句，这个tot 值 每次循环都会把第三段的值相加
- 第一次循环0加$3 ,第一行的第三段加 第二行的第三段 以此类推，最后求和一列
- 第三段所有的和 怎么求
```
[[email protected] awk]# awk -F ‘:‘ ‘{(tot=tot+$3)}; END {print tot}‘ test.txt
11685
[[email protected] awk]#
```
# 扩展
- 把这里面的所有练习题做一下
- http://www.apelearn.com/study_v2/chapter14.html
时间： 2024-10-15 15:29:40