The grep of the Linux command

1: Display the line with the root character in the/etc/passwd

1 grep ' Root ' /etc/passwd21: root:x:0:0: root:/root:/bin/Bash  3: operator:x: One:0: Operator:/root:/sbin/nologin

2: The specified file (test1) reads Hello regardless of the case of the line

1 grep -in'hello'21: Hello3  3: HELLO

Description: The ' hello ' case in grep is ignored

3: Use of Locators ^

Only the first root row appears in the/etc/passwd

1[Email protected] zkero]#grep-N'Root'/etc/passwd2 1: root:x:0:0: root:/root:/bin/Bash3  One: operator:x: One:0: operator:/root:/sbin/Nologin4[Email protected] zkero]#grep-N'^root'/etc/passwd5 1: root:x:0:0: Root:/root:/bin/bash

^ within [] is the inverse selection, outside [] is the locator

4: Display line end word represented descriptor row

1 grep ' bash$ ' /etc/passwd21: root:x:0:0: root:/root:/bin/Bash  3: zkero:x: $: Zkero:/home/zkero:/bin/bash

5: Position display blank line

1[Email protected] zkero]#Cat-N test12      1Hello3      2 World4      3HELLO5      4    6      5 World7      6    8      7I an Supker9      8I like computer!Ten      9     One[Email protected] zkero]#grep-N'^$'test1 A 4: - 6: - 9:

6: General script files have blank lines and lines at the beginning of the # comment, and omit these lines if special needs are required:

 1 [[email protected] zkero]# cat /etc/ sysctl.conf 2# Kernel SYSCTL Configurationfile  forRed Hat Linux3 #4# for binary values,0is disabled,1is enabled. See Sysctl (8) and5# sysctl.conf (5) for  Moredetails.6 7 # Controls IP packet forwarding8Net.ipv4.ip_forward =09 Ten # Controls Source Route verification OneNet.ipv4.conf.default.rp_filter =1 A  - # do not accept source routing -Net.ipv4.conf.default.accept_source_route =0 the  - # Controls The System Request debugging functionality of the kernel -KERNEL.SYSRQ =0 -  + # Controls Whether core dumps would append the PID to the core filename. -# useful forDebugging multi-threaded applications. +Kernel.core_uses_pid =1 A  at # Controls the use of TCP syncookies -Net.ipv4.tcp_syncookies =1 -  - # Disable NetFilter on bridges. -Net.bridge.bridge-nf-call-ip6tables =0 -Net.bridge.bridge-nf-call-iptables =0 inNet.bridge.bridge-nf-call-arptables =0 -  to # Controls The default maxmimum size of a mesage queue +KERNEL.MSGMNB =65536 -  the# Controls The maximum size of a message,inchbytes *Kernel.msgmax =65536 $ Panax Notoginseng# Controls The maximum shared segment size,inchbytes -Kernel.shmmax =68719476736 the  +# Controls The maximum number of shared memory segments,inchpages AKernel.shmall =4294967296 the[Email protected] zkero]#grep-V'^$'/etc/SYSC +sysconfig/sysctl.conf -[email protected] zkero]# grep-V'^$'/etc/sysctl.conf |grep-V'^#' $Net.ipv4.ip_forward =0 $Net.ipv4.conf.default.rp_filter =1 -Net.ipv4.conf.default.accept_source_route =0 -KERNEL.SYSRQ =0 theKernel.core_uses_pid =1 -Net.ipv4.tcp_syncookies =1WuyiNet.bridge.bridge-nf-call-ip6tables =0 theNet.bridge.bridge-nf-call-iptables =0 -Net.bridge.bridge-nf-call-arptables =0 WuKERNEL.MSGMNB =65536 -Kernel.msgmax =65536 AboutKernel.shmmax =68719476736 $Kernel.shmall =4294967296

The grep of the Linux command