Thread: Shell script that will install rar on linux

Hi...
I am learning shell scripting for fun and doing some automation
its very simple but useful for me..
please tell me , how I can improve this code ?
I thought of finding Distro and then installing the one specified for that Distro, but the commands used will work on every distro

PHP Code:

#!/bin/bash
# simple bash script that will install rar
# vamsi
# http://www.cyberciti.biz/faq/open-rar-file-or-extract-rar-files-under-linux-or-unix/
echo "This script will install rar on your box"
echo "The installation will begin in 5 seconds"
echo "Press Ctrl+C to cancel"
sleep 5
# go to a temp directory
cd /tmp
# detecting the architecture
if $(uname -a | grep 'x86_64'); then
  echo "this is 64 bit os, so lets install 64bit winrar"
  wget http://rarlab.com/rar/rarlinux-x64-3.8.0.tar.gz
  tar -zxvf rarlinux-x64-3.8.0.tar.gz
  cd rar
  ./unrar
else
  echo "this is 32 bit os, so lets install 32bit winrar"
  wget http://www.rarlab.com/rar/rarlinux-3.8.0.tar.gz
  tar -zxvf rarlinux-3.8.0.tar.gz
  cd rar
  ./unrar
fi
cp rar unrar /bin
echo "rar sucessfully installed" 


Regards

you might want to improve on that considering next time, the version might change. Perhaps use wget to get the main page, parse it for the latest version, and then download it.

Originally Posted by ghostdog74

you might want to improve on that considering next time, the version might change. Perhaps use wget to get the main page, parse it for the latest version, and then download it.

May be add $version and just get it on fly:

Code:

arch="x64"
version="3.8.0"
url="http://rarlab.com/rar/rarlinux-$arch-$version.tar.gz"

# down somewhere 
wget "$url"

no, that's not what i meant. if the latest version becomes 3.9, i don't want to edit the script to change the values. I want the script to detect the latest version automatically.

I think, the main problem with auto-detection is lack of standard format. There should some sort of XML format that include version and ftp location. Sure you can write kungfu using curl / sed / lynx and friends. but what if destination web page author changed his / her page layout or moved to another domain? The script will fail. There are a few solutions (and there may be more...):

1. Use a config. Only edit the same. Include this file in your script.
2. Use a Makefile file. Only edit the same. This is what FreeBSD ports does and it works quite nicely.
3. Write your kungfu script with some sort of fallback solution.