on ubuntu i just compiled my first program using lazarus and i can open it in terminal fine but if i double click the file simply marked 'hello' nothing happens. any idea why?

here is the source:

If you run a program like this from the GUI, there is no place to display the output. In the terminal, the terminal window is designated as the standard output, and so you see the results of the program.

I have not exactly the same, but a similar problem with GUI applications. They work fine on the machine they were developed on with Lazarus / Free Pascal, but after moving to another machine nothing happens after clicking.

That is the main reason why I distribute my open source applications for Linux as sourcecode only, however the situation is quite dissatisfactory.

I guess you are missing some libraries on the other machine. Try:
in a terminal and look for error messages.

If the libraries aren't there you have to install them.
That is why program depend on libraries or other programs, which sometimes leads to dependency hell.

Compiling from source isn't that bad either, many packages are distributed that way to be sure they will run once succesfully compiled.

jlinkels

Thanks for the hint. However, the problem is that the application is not even recognized as a program. Double clicking reveals a dialog box asking to select an application to open the application with.

Sorry, this may be an all too simple beginner's question. I am familiar with Mac and Windows, but not so experienced with Linux. I am sure that there is a trivial solution, but I simply can't find it out.

Open a console. Move to the directory where your file is located.
Enter ls -l youfilename
When the file is displayed you should see somthing like this in the first column:
-rwxr-xr-x
If the 'x'es aren't there, Linux does you program consider not executable. It is this bit at nothing else (not .exe or so) what makes a program executable.
If the x is not there, do:
chmod ug+x yourfilename
Now the user (owner) and group the file is owned by can execute.
Call it from the command line:
./yourfilename
and look for error messages.

jlinkels

For most people, that probably should be , as '.' will not be in $PATH.

And to the OP: when in Linux land, we distinguish between opening a file and executing or running a program or script. If a file is executable (and jlinkels has explained how to give it executable attributes), we run the program (as opposed to opening the file). Opening a file generally means something different, and implies that the file is data, not code, and we are viewing or editing the file in some way.
Windows-speak and Mac-speak go out of their way to blur this difficult concept, but Linux people are bright enough to get added value from the distinction.
jlinkels also described to you the usual way of running a program. 'Double-clicking' can mean different things in different contexts, so telling someone you did that without adding the context is ambiguous. jlinkels was bright enough to detect your Windows-speak, guessed what you meant, and arrived at a likely correct answer to your problem.

--- rod.

Darn... forgot that
jlinkels