Upload File

shells, environment, scripting, and bash · typing commands into the bash shell and running a bash...

  • Home
  • Documents
  • Shells, Environment, Scripting, and Bash · Typing commands into the bash shell and running a bash script are the same $ cat test.sh echo "hello" > test cat test true && echo "hello"
17
Shells, Environment, Scripting, and Bash (in 80 minutes[!]) Pat Pannuto / Marcus Darden

Upload: others

Post on 12-Oct-2020

22 views

Category:

Documents


0 download

Report

TRANSCRIPT

Page 1: Shells, Environment, Scripting, and Bash · Typing commands into the bash shell and running a bash script are the same $ cat test.sh echo "hello" > test cat test true && echo "hello"

Shells,Environment,Scripting,andBash

(in80minutes[!])

PatPannuto/MarcusDarden

http://creativecommons.org/licenses/by/4.0/
http://patpannuto.com/
Page 2: Shells, Environment, Scripting, and Bash · Typing commands into the bash shell and running a bash script are the same $ cat test.sh echo "hello" > test cat test true && echo "hello"

Q:Howdoesaprogramstart?

Page 3: Shells, Environment, Scripting, and Bash · Typing commands into the bash shell and running a bash script are the same $ cat test.sh echo "hello" > test cat test true && echo "hello"

Q:Howdoesaprogramstart?Thejobsofashell

Spawn(launch)newprogramsHandleinputandoutputtoprogramsKillandcleanupoldprograms

Page 4: Shells, Environment, Scripting, and Bash · Typing commands into the bash shell and running a bash script are the same $ cat test.sh echo "hello" > test cat test true && echo "hello"

Q:Howdoesaprogramstart?Thejobsofashell

Spawn(launch)newprogramsHandleinputandoutputtoprogramsKillandcleanupoldprograms

Whatshellshaveyouused?

Page 5: Shells, Environment, Scripting, and Bash · Typing commands into the bash shell and running a bash script are the same $ cat test.sh echo "hello" > test cat test true && echo "hello"

Let'spokearoundhowthe[Desktop]shellworks

$cp/usr/share/applications/firefox.desktop~/Desktop/

$chmod+x~/Desktop/firefox.desktop

Page 6: Shells, Environment, Scripting, and Bash · Typing commands into the bash shell and running a bash script are the same $ cat test.sh echo "hello" > test cat test true && echo "hello"

Let'spokearoundhowthe[Desktop]shellworks

$cp/usr/share/applications/firefox.desktop~/Desktop/

$chmod+x~/Desktop/firefox.desktop

Whatmakesfirefox.desktop work?

Page 7: Shells, Environment, Scripting, and Bash · Typing commands into the bash shell and running a bash script are the same $ cat test.sh echo "hello" > test cat test true && echo "hello"

Let'spokearoundhowthe[Desktop]shellworks

$cp/usr/share/applications/firefox.desktop~/Desktop/

$chmod+x~/Desktop/firefox.desktop

Whatmakesfirefox.desktop work?

Howdoesthe[desktop]shell:Spawn(launch)newprogramsHandleinputandoutputtoprogramsKillandcleanupoldprograms

Page 8: Shells, Environment, Scripting, and Bash · Typing commands into the bash shell and running a bash script are the same $ cat test.sh echo "hello" > test cat test true && echo "hello"

Let'spokearoundhowthe[bash]shellworks

$firefox

<Ctrl-C>

$firefox&

$jobs

$fg

<Ctrl-Z>

$bg

$echo"hello">test

$cattest

$true&&echo"hello"

$false&&echo"nope"||echo"whaaaat?"

Page 9: Shells, Environment, Scripting, and Bash · Typing commands into the bash shell and running a bash script are the same $ cat test.sh echo "hello" > test cat test true && echo "hello"

Let'spokearoundhowthe[bash]shellworks

$firefox

<Ctrl-C>

$firefox&

$jobs

$fg

<Ctrl-Z>

$bg

$echo"hello">test

$cattest

$true&&echo"hello"

$false&&echo"nope"||echo"whaaaat?"

Howdoesthe[bash]shell:Spawn(launch)newprogramsHandleinputandoutputtoprogramsKillandcleanupoldprograms

Page 10: Shells, Environment, Scripting, and Bash · Typing commands into the bash shell and running a bash script are the same $ cat test.sh echo "hello" > test cat test true && echo "hello"

Where'sfirefox anyway?$firefox#Thisworks

$gcchello.c-ohello#Thisworks

$hello#Thisdoesn't

$./hello#Thisworks

YourenvironmentaffectsprogrambehaviorEvenshells!(they'reaprogramtoo)

Page 11: Shells, Environment, Scripting, and Bash · Typing commands into the bash shell and running a bash script are the same $ cat test.sh echo "hello" > test cat test true && echo "hello"

Changingtheenvironmentwillchangeprogrambehavior

Inthiscase,howashellperformsthesearchforprograms

$PATH=$PATH:/home/username/#Assuming"hello"isinthisfolder

$hello#Nowthisworks!

$PATH=/home/username#Whatifyou'ddonethisinstead?

Alsosawabriefexampleofenvironmentvariablesinlastweek'shomework

Page 12: Shells, Environment, Scripting, and Bash · Typing commands into the bash shell and running a bash script are the same $ cat test.sh echo "hello" > test cat test true && echo "hello"

Yourprogramscanusetheenvironmenttoo

#include<iostream>

usingnamespacestd;

intmain(intargc,char*argv[],char*envp[]){

cout<<"argc:"<<argc<<endl;

cout<<"envp[0]:"<<envp[0]<<endl;

//while(*envp++){//Trythisone,too!

//cout<<*envp<<endl;

//}

return0;

}

$./a.out

$HELLO=world./a.out

$lower=finemany=okaytoo./a.out

$exportIamPermanent=ish

$./a.out

$#Tryuncommentingthewhileloop,didyoufindthemissingones?

$./a.out|less#Thismayexplainsomeofthefunnycolors

Page 13: Shells, Environment, Scripting, and Bash · Typing commands into the bash shell and running a bash script are the same $ cat test.sh echo "hello" > test cat test true && echo "hello"

Nowwhataboutscripting?

Page 14: Shells, Environment, Scripting, and Bash · Typing commands into the bash shell and running a bash script are the same $ cat test.sh echo "hello" > test cat test true && echo "hello"

Nowwhataboutscripting?Surprise!You'vebeenscriptingthiswholetime!

Typingcommandsintothebashshellandrunningabashscriptarethesame

$cattest.sh

echo"hello">test

cattest

true&&echo"hello"

false&&echo"nope"||echo"whaaaat?"

$chmod+xtest.sh#Whatisthisdoing?

$./test.sh

Page 15: Shells, Environment, Scripting, and Bash · Typing commands into the bash shell and running a bash script are the same $ cat test.sh echo "hello" > test cat test true && echo "hello"

Nowwhataboutscripting?Surprise!You'vebeenscriptingthiswholetime!

Typingcommandsintothebashshellandrunningabashscriptarethesame

$cattest.sh

echo"hello">test

cattest

true&&echo"hello"

false&&echo"nope"||echo"whaaaat?"

$chmod+xtest.sh#Whatisthisdoing?

$./test.sh

Howtowriteabashscript?

TrythingsoutintheterminalCopythingsthatworkintoafile($history)RunthatfileRepeat

Page 16: Shells, Environment, Scripting, and Bash · Typing commands into the bash shell and running a bash script are the same $ cat test.sh echo "hello" > test cat test true && echo "hello"

Bashisold...Butuseful,especiallyforreallyshortthings

ButhasuglyandfinickysyntaxVARIABLE=test != VARIABLE=test :(

Butrunningprogramsisreallyeasy(it'swhatitwasbuiltforafterall)g++-O3-m32thread.olibinterrupt.atest1.cpp-ldl-otest1

./test1

ButdoingmuchmoreistrickyValidateprogramoutput( diff ?),whatifitvaries?Ruleofthumb:Morethan50-100lines,morethanashellscript

Page 17: Shells, Environment, Scripting, and Bash · Typing commands into the bash shell and running a bash script are the same $ cat test.sh echo "hello" > test cat test true && echo "hello"

ClosingremarksTryoneoftheAdvancedExercises

We'reattheendofSegment1

Reminder:YoumustsubmittostaffatOH


Hello Narwhals! 1 9 19.pdf · Hello Narwhals! Today is Tuesday, September 19th. It is D Day on your schedule. ... things like the Siesta Sofa Air Chair and the VIP Party Bingo Bash!

Andreas Buzh Skau [email protected] Research Computing ...folk.uio.no/buzh/bash/Shellscripting-slides-fall2015.pdf · echo "Welcome to the tutorial, $WHO" echo "$DATE" Simple script:

Programacion Bash

Shell ScriptingShell Scripting I A sequence of system programs carrying out a speci c task I The simplest script is: #!/bin/bash echo Hello World; ls ~/ |fmt -w 40 I \#" indicates

Introduction to the Bash Shell - College of Computing ... › ~kschmidt › CS571 › Lectures › Bash › bas… · Introduction to the Bash Shell Kurt Schmidt Shell–Bash set,

Bash Reference Manual - freeinfosociety.com · Bash Reference Manual Reference Documentation for Bash Edition 3.2, for Bash Version 3.2. September 2006 Chet Ramey, Case Western Reserve

Docker –bringt‘s was?€¦ · docker run --name backgroundContainer -d ubuntu /bin/bash \-c "while true; do echo hello world; sleep 1; done" # Get the logs (-f for continuous

bash vs. dash - jpsdomain.org · bash vs dash bash ... – "checkbashisms: check whether a /bin/sh script contains any common bash-specific constructs" checkbashisms! $ checkbashisms

Red Hat Enterprise Linux 7 RPM パッケージングガ …...bash で書かれた Hello World: bello Python で書かれた Hello World: pello.py C で書かれた Hello World: cello.c

Bash Linux

echo - Print Text to the Terminalckelly/teaching/common/lecture/...echo - Print Text to the Terminal •echo simply prints whatever comes after it to the terminal $ echo Hello world!

Bash Shell7

bash vs. dash - princessleia.com · if ls then pwd elif cd /tmp then echo ok else echo no fi. Works in both Standard case statements case $X in ... bash dash shell portability Linux

bash vs. dash - PrincessLeia.comprincessleia.com/plug/2008-JP_bash_vs_dash.pdf · /bin/sh --> dash, default user shell still bash ... bash vs dash bash

DECEMBER 2010 curves - Echo Foundationechofoundation.co.za/.../11/hello-echo-2010_12.pdf · dumped in the sea near Mossel Bay. He was rescued there and sent on to SAMREC for care,

Dockah, Dockah, Dockah - People 101 Hello, World! $> docker run rhel7 echo “Hello, World!” Fetch an image $> docker pull rhel6 List images $> docker images 29 Dockerfile Simple

Changes in Bash Version 4.2 to Bash 4.3

ECHO Büromöbel · ECHO Büromöbel - ECHO Cubos-Tische - ECHO Vario-Tische - ECHO City Office Tische - ECHO Forum Konferenz - ECHO Progress - ECHO Modul - ECHO Impressionen - ECHO

Hello Narwhals! - Downingtown Area School District / Homepage 10 26.pdf · Hello Narwhals! Today is Thursday, ... ndis the VIP PARTY BINGO BASH during 2 period in the ... TODAY during

Intermediate shell scripting in BASH - folk.uio.nofolk.uio.no/buzh/bash/old/fall2012.pdf · Intermediate shell scripting in BASH ... be used to execute the script: /bin/bash ... Advanced

Bash Lecture 1 Bash and Linux command line introduction

Bash - cisco.com · (Bash).Bashinterpretscommandsthatyouenterorcommandsthatarereadfromashellscript.UsingBash enablesaccesstotheunderlyingLinuxsystemonthedeviceandtomanagethesystem

Bash intro

Birthday Bash!

Shell Scriptingcgi.di.uoa.gr/~ad/k24/set002.pdf · Shell Scripting I A sequence of system programs carrying out a speci c task I The simplest script is: #!/bin/bash echo Hello World;

Bash script

Container-Virtualisierung DDOOCCKKEERR · docker run --name "hello-world" ubuntu echo "Hello World!" run-Kommando legt die Container-Kon guration fest Unable to find image 'ubuntu:latest

bash. Wprowadzenie

Bash Programming

bash - UNIXwebcourse.cs.technion.ac.il/234122/Spring2014/ho/WCFiles/tutorial2.pdf · ˘script - ) Bash ˚ # # source ˚ Shell- ˘ ˚ 4 234122 - ˘ echo Running test 1

Shells. Variables MESSAGE="HELLO WORLD" echo $MESSAGE MESSAGE="HELLO WORLD $LOGNAME" echo $MESSAGE MESSAGE="HELLO WORLD $USER" echo $MESSAGE

Bash Scripting - classes.eastus.cloudapp.azure.comclasses.eastus.cloudapp.azure.com/.../comp190/lecture/bash-inter.pdf · #!/bin/bash # term_size2 -Dynamically display terminal window

Bash Prompt HOWTO - The Linux Documentation Project may not work with Bash 1.x. You can check your Bash version by typing echo $BASH_VERSION at the prompt. On my machine, it responds

2011.rubyworld-conf.org2011.rubyworld-conf.org/files/slides/Key-3.pdf · $ mkdir hello $ cd hello $ echo -e “require ‘sinatra’\\nget ‘/’ do \“Hello\” end” > hello.rb

Lecture 6: Using BASH Effectivelymath.iit.edu/~mccomic/2042/lectures/lecture6.pdfMore About BASH Screen Variables Making BASH Work for You Pattern Matching (Globbing) BASH and Variables