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to run CGI programs, or you may have problems with standard output. With Apache Web Server, you can have a first line in your program of:

1. !.\eui.exe to run your program using eui.exe in the current (cgi-bin) directory. Be careful that your first line ends with the line breaking characters appropriate for your platform, or the ! won't be handled correctly. You must also set the execute permissions on your program correctly, and ex.err and ctrace.out must be writable by the server process or they won't be updated.

Read / Write Ports?

How do I read/write ports?

There are collections of machine-level routines from the Euphoria Web Page.

Program has no errors, no output

When I run my program there are no errors but nothing happens.

You probably forgot to call your main procedure. You need a top-level statement that comes after your main procedure to call the main procedure and start execution.

Routine not declared

I'm trying to call a routine documented in library.doc, but it keeps saying the routine has not been declared.

Did you remember to include the necessary .e file from the euphoria\include directory? If the syntax of the routine says for example, "include\std\graphics.e", then your program must have "include\std\graphics.e" (without the quotes) before the place where you first call the routine.

Routine not declared, my file

I have an include file with a routine in it that I want to call, but when I try to call the routine it says the routine has not been declared. But it has been declared.

Did you remember to define the routine as public, export or possibly global? If not, the routine is not visible outside of its own file.

After user input, left margin problem

After inputting a string from the user with gets, the next line that comes out on the screen does not start at the left margin.

Your program should output a new-line character e.g.

input = gets() 
puts(SCREEN, '\n') 

Floating-point calculations not exact

Why aren't my floating-point calculations coming out exact?

Intel CPU's, and most other CPU's, use binary numbers to represent fractions. Decimal fractions such as 0.1, 0.01 and similar numbers can't be represented precisely. For example, 0.1 might be stored internally as 0.0999999999999999 . That means that 10 * 0.1 might come out as 0.999999999999999, and floor(10 * 0.1) might be 0, not 1 as you would expect. This can be a nuisance when you are dealing with money calculations, but it is not a Euphoria problem. It's a general problem that you must face in most programming languages. Always remember: floating-point numbers are just an approximation to the "real" numbers in mathematics. Assume that any floating-point calculation might have a tiny bit of error in the result.