Exiting from a function or procedure

[tmoran@bix.com]

>this program i have a procedure that must do something if it's parameters
>meet a certain condition; otherwhise it must exit.
  Do you mean the procedure must exit in the sense of return, or exit
in the sense of stopping the program?  Your C examples suggests the
latter.
  You could use "pragma import" on the C "exit" procedure and just
call it, exactly as your C program does.  Your code using an exception
is fine except that it catches the exception, prints the error message,
and then tries to drop out the bottom of the function without returning
any value.  You probably want to add a "raise;" statement after
the Put, to re-raise the exception.
  Note also that some compilers are only half-smart and will give a
warning on the construct
     if ... then ... return some_value;
     else ... raise some_exception;
     end if;
   end some_function;
because the compiler realizes that if the program takes the "else"
branch it will drop out the bottom of the function without returning
any value, but the compiler doesn't realize that some_exception will
be raised and prevent reaching the bottom of the function.