Re: Timeouts in Ada

["Randy Brukardt" <randy@rrsoftware.com>]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 1495 bytes --]

"J-P. Rosen" <rosen@adalog.fr> wrote in message 
news:lq7uhv$vao$1@dont-email.me...
> Le 17/07/2014 07:18, NiGHTS a écrit :
>> I am looking at Ex. 10.
>>
>>   task Password_Server is
>>      entry Check (User, Pass : in String; Valid : out Boolean);
>>      entry Set (User, Pass : in  String);
>>   end Password_Server;
>>   ...
>>   User_Name, Password : String (1 .. 8);
>>   ...
>>   Put ("Please give your new password:");
>>   Get_Line (Password);
>>   select
>>      Password_Server.Set (User_Name, Password);
>>      Put_Line ("Done");
>>   or
>>      delay 10.0;
>>      Put_Line ("The system is busy now, please try again later.");
>>   end select;
>>
>> Now as an Ada beginner with a strong background in C/Asm I interpret
>> this example in the following way...
>>
>> 1. "select" creates a thread which runs the body of "select" or the
>> body of "or". Or maybe it creates two threads for each and blocks its
>> own thread until one finishes.
>>
> [Rest snipped, since based on wrong assertion]
>
> Not at all! In Ada, one task=one thread, there are no hidden threads.

Not true; ATC may need a hidden thread. But not here... (well, not unless 
the task supervisor itself uses a hidden thread, but that would probably 
exist during the life of the program).

> This kind of select is called a timed entry call.

Oops, you are right. For some reason, I thought this was an ATC. Ignore my 
previous response (unless you're thinking about ATC).

                              Randy.