Linux system startup process and scripting (3)

Linux system startup process and scripting (3)

1. Special variable values

${variable argument #* character} means left to right, with "character" as the delimiter, taking all strings after the first delimiter

${variable argument ##* character} means left to right, with "character" as the delimiter, taking all strings following the last delimiter

${variable parameter% character *} means right-to-left, with "character" as the delimiter, taking all strings after the first delimiter

${variable parameter the percent character *} means right-to-left, with "character" as the delimiter, taking all strings following the last delimiter

${#变量名} means the numeric value of a string in the calculation variable

For example: Suppose the variable a= "10 23 45 56", with a blank delimiter, take out the following different values

650) this.width=650; "src=" http://s3.51cto.com/wyfs02/M01/7F/9E/wKioL1clyWfBzFUNAAFPtGjcv8s680.jpg "title=" aa.jpg "alt=" Wkiol1clywfbzfunaafptgjcv8s680.jpg "/>

The basic sequence of script calls for 2.linux systems is as follows:

2.1:init master process, read/etc/inittab configuration file

2.2. From the/etc/inittab configuration file, set the default run level

2.3. From the/etc/inittab configuration file, execute the/etc/rc.d/rc.sysinit script file

2.4. From the/etc/inittab configuration file, execute a script that specifies the run level

such as:/etc/rc.d/rc->/etc/rc.d/rc[0-6].d/*->/etc/rc.d/init.d/*, the layers are called sequentially

2.5. Finally execute the/etc/rc.d/rc.local script

3. Customize an external command, such as Ls,useradd,mount commands, and each command relies on its own library file,

Write a script like this to automate the copy of the external command from the existing system and copy the corresponding library file

#!/bin/bash

Dest=/mnt/sysroot

LIBCP () {

libpath=${1%/*}

[!-D $DEST $libpath] && mkdir-p $DEST $libpath

[!-e $DEST ${1}] && cp $DEST $libpath && echo "is coped successfully"

}

BINCP () {

cmdpath=${1%/*}

[!-D $DEST $cmdpath] && mkdir-p $DEST $cmdpath

[!-e $DEST ${1}] && cp $DEST $cmdpath

For LIB in ' LDD $ | Grep-o "/.*lib\ (64\) \{0,1\}/[^[:space:]]\{1,\}"; Do

LIBCP $LIB

Done

}

Read-p "Please Input need add command:" CMD

until [$CMD = = ' Q ']; Do

if! which $CMD &>/dev/null; Then

Ehco "Your command is not exist ..."

Read-p "Please Input need add Command,again:" CMD

Continue

Fi

Command= ' which $CMD | Grep-v "^alias" | Grep-o "[^[:space:]]\{1,\}" '

BINCP $COMMAND

echo "$COMMAND is copied OK"

Read-p "Please Input need add command:" CMD

Done

4. Customize a switch machine script, name:/etc/rc.d/init.d/halt

#!/bin/bash

Case $ in

*reboot)

Command= '/sbin/reboot ';;

*halt)

Command= '/sbin/halt-p ';;

*)

echo "by *halt | *reboot "

;;

Esac

Case $ in

Start

;;

Stop

;;

*)

echo "Usage: ' basename $ ' {start|stop}"

;;

Esac

EXEC $COMMAND

~

5. Custom-made one in the system switch or service switch when the display OK is green, failed is a red script

Script Name:/etc/rc.d/init.d/functions

#!/bin/bash

screen= ' stty-f/dev/console size 2>/dev/null '

columns=${screen#*}

[-Z $COLUMNS] && columns=80

spa_col=$[$COLUMNS-14]

Red= ' \033[31m '

Green= ' \033[32m '

yellow= ' \033[33m '

Blue= ' \033[34m '

Normal= ' \033[0m '

Success () {

String=$1

rt_col=$[$SPA _col-${#string}]

Echo-n "$string"

For I in ' seq 1 $RT _col '; Do

Echo-n ""

Done

Echo-e "[${green}ok${normal}]"

}

Failure () {

String=$1

rt_col=$[$SPA _col-${#string}]

Echo-n "$string"

For I in ' seq 1 $RT _col '; Do

Echo-n ""

Done

Echo-e "[${red}failed${normal}]"

}

~

Note: This script can also be set up as a configuration file for other script calls to use

6. Customize a network startup script, name:/etc/rc.d/init.d/network

#!/bin/bash

# CHKCONFIG:35 10 89

# Description:netwrok Service

Prog=network

. The service color script file is displayed above the/etc/rc.d/init.d/functions call (note that the first row is deleted when called)

Conf=/etc/sysconfig/network-scripts/ifcfg-eth0

. $CONF

Start () {

Ifconfig eth0 $IPADDR/$NETMASK up

[-Z $GATEWAY] && route add default GW $GATEWAY

}

Stop () {

Ifconfig eth0 Down

}

Status () {

Ifconfig eth0

}

Usage () {

echo "Usage: $prog: {start|stop|restart|status}"

}

Case $ in

Start

Start

Success "Config Network Eth0"

;;

Stop

Stop

Success "Stop Network Eth0"

;;

Restart

Stop

Start

Success "Restart Network Eth0"

;;

Status

Status

;;

*)

Usage

Exit 5

;;

Esac

7. Customize a system initialization script/etc/rc.d/rc.sysinit

[Email protected] sysroot]# vim Etc/rc.d/rc.sysinit

#!/bin/bash

. Etc/rc.d/init.d/functions

Echo-e "\ t Welcome to \033[31mwillow person\033[0m Linux ..."

echo "Remount rootfs ..."

Mount-n-O REMOUNT,RW/

Mount-a

[$?-eq 0] && Success "mount other system files" | | Failure "Mount Other system files"

echo "Set the hostname ..."

#[-f/etc/sysconfig/network] && source/etc/sysconfig/network

[-f/etc/sysconfig/network] &&. /etc/sysconfig/network

[-Z $HOSTNAME-o $HOSTNAME = = ' (none) '] && hostname=localhost

/bin/hostname $HOSTNAME

Insmod/lib/modules/mii.ko

[$?-eq 0] && Success "Loading modules Mii" | | Failure "Loading Modules Mii"

Insmod/lib/modules/pcnet32.ko

[$?-eq 0] && Success "Loading modules Pcnet32" | | Failure "Loading Modules Pcnet32"

#ifconfig eth0 1.1.1.100

Ifconfig Lo 127.0.0.1

#/bin/bash

/sbin/sysctl-p

7. Customize a basic Service script: Name:/etc/rc.d/init.d/xserver

#!/bin/bash

# CHKCONFIG:35 68 31

# Description:tserve Script Service

. /etc/rc.d/init.d/functions

#prog = ' basename '

Prog=tserver

lockfile=/var/lock/subsys/$prog

Start () {

# echo "Starting $prog ..."

Touch $lockfile

[$?-eq 0] && Success "Starting $prog" | | Failure "Starting $prog"

}

Stop () {

# echo "Stopping $prog ..."

[$?-eq 0] && Success "Stopping $prog" | | Failure "Stopping $prog"

RM-RF $lockfile

}

Status () {

If [-f $lockfile]; Then

echo "$prog is Running ..."

Else

echo "$prog is Stopped ..."

Fi

}

Usage () {

echo "Usage: $prog {Start|stop|status|restart}"

}

Case $ in

Start

start;;

Stop

stop;;

Restart

Stop

Start

;;

Status

Status

;;

*)

Usage

Exit 6

;;

Esac

This article is from the "Xavier Willow" blog, please be sure to keep this source http://willow.blog.51cto.com/6574604/1769355

Linux system startup process and scripting (3)