Re: Ada Tasks and Keyboard I/O

[kilgallen@eisner.decus.org (Larry Kilgallen)]

In article <33A12825.1C80@onlink.net>, "David H. Haley" <dhaley@onlink.net> writes:
> I have developed a software package in Ada and thought it would be nice
> to have the time perodically updated on the screen while waiting for the
> user to input a value from the keyboard.
> 
> This "sounds" easy enough to do using tasks; however, once the program
> reaches the Get(My_Number) statement all other tasks come to a grinding
> halt waiting for this keyboard I/O to occur <grr>.

From an Ada perspective, your task with the "Get" is still computing.

Some compilers support pragma TIME_SLICE to alleviate this for
equal priority tasks, depending on operating system constraints.

> Any ideas how I can accomplish the requirement in para 1 ? I am using 
> Meridian OpenAda Dos ver 4.1.4, an ADA 83 compiler.
                   ^^^
Your program must be doing what the operating system views as
asynchronous I/O, so if you insist on DOS it may be that you
must use an add-on OS extender that makes it behave less like
DOS.  Some Ada compilers come with such extenders.

Larry Kilgallen