[SOLVED] Bash'ing myself over the head, yes,no prompt scripting issues :(

Astroe · 11-20-2011, 07:17 PM

Hey there, so I'm writing a script that will automate the download and most of the install of Java JDK, Android SDK, Eclipse, and script adb to start at boot.

If you own an Android phone, this would mean that you could view and manipulate your phone from your Ubuntu computer.

So I've got most of the script done, but I'm having issues with the prompts.

So when the script gets to the point where it edits the .bashrc I'd like it to stop and ask the user if they want to do that. I found the script for a prompt that works here and it looks like this

Code:

#1/bin/bash
yn() {
printf " Reply [y/n]: "
read yn
[[ "$yn" != y ]] && [[ "$yn" != n ]] && yn
}
# OTHER CODING
# Now you pose a question
# and then execute the yn function

printf "do you want to continue, "
yn
[[ "$yn = n ]] && exit

This is the unaltered code from the forum post, not yet customized to my needs.
What I want it to do it, if they say no, then the script continues, just skips the command that's tied to yes.
I also need to script it so that if they say no, it doen't give them the

Code:

echo "Congratulations, you're almost there!"

message.

Any help anyone can offer is appreciated

grail · 11-20-2011, 07:50 PM

So I am guessing the typo in the first line is a known (ie should be ! not 1) Also you seem to be missing quotes in the final test.

So you have said what you would like ... what issues are you having? Are you not being prompted at the correct point? Are you still getting the congrats after pressing n?

Astroe · 11-20-2011, 08:07 PM

Oh, ok so I started fiddling with it, ended up with this,

Code:

# Yes/No Prompt BASH
yn() {
printf " Reply [y/n]: "
read yn
[[ "$yn" != y ]] && [[ "$yn" != n ]] && yn
}
# OTHER CODING
# Now you pose a question
# and then execute the yn function

printf "If you'd like to install the android screencaster press y, otherwise press n."
yn
[[ $yn = y ]] && sudo wget -P ~/android-sdks/platform-tools http://androidscreencast.googlecode.com/svn/trunk/AndroidScreencast/dist/androidscreencast.jnlp && sudo chmod +x ~/android-sdks/platform-tools/androidscreencast.jnlp && echo "That's awesome! Now you have the screen caster! You can run it by using the following commands from a Terminal, in order" && echo "cd ~/android-sdks/platform-tools" && echo "javaws androidscreencast.jnlp"

And I think this bit will download the android screencast and make it executable. The folder it's being downloaded to has already been added to the .bashrc in a previous step so they'd be able to use it by just typing

Code:

javaws androidscreencast.jnlp

into the terminal.

But yeah, I was having trouble because I didn't think to add && and make yes give a string of commands. Think it's under control now though, thanks

grail · 11-20-2011, 08:33 PM

Personally, when I require more than one command after the test I would use an if instead of && or || constructs (there are dangers with them that may not seem obvious).
So as an alternative:

Code:

if [[ $yn = y ]]
then
    sudo wget -P ~/android-sdks/platform-tools http://androidscreencast.googlecode.com/svn/trunk/AndroidScreencast/dist/androidscreencast.jnlp
    sudo chmod +x ~/android-sdks/platform-tools/androidscreencast.jnlp
    echo "That's awesome! Now you have the screen caster! You can run it by using the following commands from a Terminal, in order"
    echo "cd ~/android-sdks/platform-tools"
    echo "javaws androidscreencast.jnlp"
fi

Also you may wish to consider what happens when the user enters an incorrect value or even a case altered one (ie Y instead of y)

Here are a couple of helpful links to get you going:

http://tldp.org/LDP/abs/html/
http://mywiki.wooledge.org/TitleIndex

Astroe · 11-20-2011, 08:47 PM

Thanks

Those links will definitely come in handy in the future.

This scripts is just for a few classmates though, and doing the entire thing manually isn't that hard, I'm just trying to make it simpler, not baby-proof it