Shulou(Shulou.com)06/01 Report--

Ps: a command that displays the current process status of the system

Ps an all terminal-related processes

Ps x all terminal-independent processes

Ps u displays process-related information user-centric

VSZ:

Virtual memory set, Virutal menmory Size

RSS:

Resident memory set

STAT:

R: running or runnable

S: interruptible sleep

D: uninterrupted sleep

T: stop

Z: zombie

S:session leader has child processes

+: foreground process

L: multithreaded process

N: low priority proc

Backstage. Ctrl+z sends the foreground job to the background, and the job is "stopped".

If it is not already started: COMMAND &

If you exit the current session, the job will also be terminated, because the job is related to the current terminal. If you send the job to the background, you do not expect the job to stop with the termination.

Nohup COMMAND &

How to make the job sent to the background continue to execute:

Fg [[%] Job number]: transfer the job back to the front desk to continue

Bg [[%] Job number]: let the job continue in the background

The default is the last task to enter the background

Kill% Job number: terminate the job

Check the assignment number:

Jobs

Pmap pid to view the memory footprint of a process

00007fb60640d000 4K rw--- / sbin/init

Starting address space permission

Bash script programming: the case statement of

The syntax format of the case statement:

Case expression in

Pattern1)

Suite1

Pattern2)

Suite2

...

Patternn)

Suiten

*)

Other_suite

Esac

Modes are available for each pattern in case:

A | b an or b

* match any character of any length

? Match any single character

[-] range matching

Exercise: write a script and accept this format

Script.sh {start | stop | restart | status}

1. If start, create / var/lock/subsys/script.sh, indicating that the startup is successful.

2. If the parameter is stop, delete / var/lock/subsys/script.sh, indicating that the stop is successful.

3. If restart, delete it, create it again, and display it successfully

4. If status, if the file exists, running is displayed, otherwise, stopped is displayed

#! / bin/bash

#

MyService= `basename $0`

LockFile= "/ var/lock/subsys/$myService"

[$#-lt 1] & & echo "Usage: $myService {start | stop | restart | status}" & & exit 4

Case $1 in

'start')

Touch $lockFile

Echo "Starting $myService OK"

'stop')

Rm-f $lockFile

Echo "Stopping $myService OK"

'restart')

Rm-f $lockFile

Touch $lockFile

Echo "Restarting $myService OK"

'status')

If [- f $lockFile]; then

Echo "$myService is running"

Else

Echo "$myService is stopped"

Fi

*)

Echo "Usage: $myService {start | stop | restart | status}"

Exit 3

Esac

Exercise: write a script that packages and backs up the / etc/ directory at the / backup/etc- date. Suffix

1. The following menu is displayed to the user:

Xz) xz compress

Gzip) gzip compress

Bip2) bzip2 compress

2. Use tar to package compression according to the compression tool specified by the user.

3. If the default is xz; input error, you need to re-enter it.

#! / bin/bash

#

[- d / backup] | | mkdir / backup

Cat / dev/null & & echo "No this interface..." & & exit 3

Read-p "Enter an alias:" ethAlias

Read-p "Enter IP:" ipAddr

Read-p "Mask:" netMask

Ifconfig $ethAlias $ipAddr netmask $netMask

[$debug-eq 1] & & ifconfig $ethAlias

Functions of bash script programming

Can be called: the function has a function name

Where the function appears, it is automatically replaced with the code defined by the function

Function definition

Syntax:

FuncName () {

Function body

}

Function FuncName {

Function body

}

A function has two return values:

Data returned normally:

Print statements in a function, such as echo or print

The execution result of the command in the function

Execution status return value:

Depends on the last statement executed in the function

Customization: return N

The function can accept parameters:

Parameters similar to script call position parameters can be used in the function body.

$1, $2.

$#

$*, $@

Exercise: write a script to perform the following functions

1. Display the following menu

Disk) show disk info

Mem) show memory info

Cpu) show cpuinfo

2. Display the content selected by the user

#! / bin/bash

#

ShowMenu () {

Cat > / dev/null

If [$?-eq 0]; then

Echo-e "\ 033 [32m$ipAddr\ 033 [0m"

Else

Echo-e "\ 033 [31m$ipAddr\ 033 [0m"

Fi

}

For i in `seq 0255`; do

For j in `seq 1 254`; do

Ping $I $j

Done

Done

Exercise: write a script to perform the following functions (using functions):

1. Prompt the user for an executable command

2. Get all the library files on which this command depends (using the ldd command)

3. Copy the command to the directory corresponding to / mnt/sysroot/

Explanation: suppose that if you copy the cat command and its executable path is / bin/cat, then copy / bin/cat to the / mnt/sysroot/bin/ directory. If you copy the useradd command and the executable path of useradd is / usr/sbin/useradd, copy it to the / mnt/sysroot/usr/sbin/ directory.

4. Copy each library file to the corresponding directory of / mnt/sysroot/, which requires a command

#! / bin/bash

#

Target=/mnt/sysroot

ClearCmd () {

If which $cmd & > / dev/null; then

CmdPath= `which-- skip-alias $cmd`

Else

Echo "No such command"

Return 5

Fi

}

CmdCopy () {

CmdDir= `dirname $1`

[- d ${target} ${cmdDir}] | | mkdir-p ${target} ${cmdDir}

[- f ${target} ${1}] | | cp $1 ${target} ${cmdDir}

}

LibCopy () {

For lib in `ldd $1 | grep-o "/ [^ [: space:]]\ {1,\}" `; do

LibDir= `dirname $lib`

[- d ${target} ${libDir}] | | mkdir-p ${target} ${libDir}

[- f ${target} ${lib}] | | cp $lib ${target} ${libDir}

Done

}

While true; do

Read-p "Enter a command:" cmd

If ["$cmd" = = 'quit']; then

Echo "quit"

Exit 0

Fi

ClearCmd $cmd

[$?-eq 5] & & continue

CmdCopy $cmdPath

LibCopy $cmdPath

Done

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