Shell Programming and Scripting

Hi all,

I'm trying at the moment to write a shell script to build a directory tree and create files within the built directories. I've scoured through sites and text books and I just can't figure out how to go about it.

I would assume that I need to use loops of some sort, but I can't seem to get it.

For example, I would have parent directory I create called "mydir" then in my dir I have 2 subdirectories "Work" and "Games". Then in "Games" I would have text files "game1.txt and game2.txt".

Any help would be greatly appreciated. Thanks!

Try looking at the man pages for the mkdir and touch utilities.

You might not need any loops.

At a minimum, you could do something using the mentioned mkdir and touch commands. Put them in a shell script, such as mkdirs.sh, like:

Code:

mkdir /home/mydir/
mkdir /home/mydir/games/
mkdir /home/mydir/work/

touch /home/mydir/games/game1.txt

Then run "chmod 755 mkdirs.sh" to set permissions. Then run "./mkdirs.sh" to run the script.

How would I additionally get the shell script to create a java file with a basic "Hello World" output?

---------- Post updated at 11:19 PM ---------- Previous update was at 10:29 PM ----------

I tried doing:

touch helloworld.java
echo "public class Helloworld { public static void main (String args []) { System.out.println(\"Hello World\"); }} >> Helloworld.java

But when I do javac on it, I get no output. Instead it tells me "Could not find the main class: Helloworld.java. Program will exit"

You don't get any output because you have mismatched double-quotes on the above echo command. Did you get a command prompt before you entered the javac command? Or, is it still waiting for you to complete the string to be echoed? Do you understand that javac doesn't run your java program; it only compiles it?

Why do I get the strong impression that you're asking us to complete a homework assignment for you?

I'm simply trying to learn the basics of unix

I made a typo in my above code. I actually do have the matching double-quotes. I also realized that javac only compiles it and that I do actually need to run the java file.

It tells me that it cannot find the main class, which I have looked up and from my understanding, it cannot find jdk and so it is giving me that error?

If you didn't have a jdk you would have gotten a diagnostic from you shell saying something like shellname: javac not found. The diagnostic you got sounds more like you tried to run the program using:

Code:

java *.class

Did you try:

Code:

ls -l

after you ran:

Code:

javac *.java

?

Did you find a file named helloworld.class? Did you try running the command java helloworld?

If you don't show us the ACTUAL commands that you run and the exact messages that are printed, any help we may try to give can only be wild guesses.