Re: HTTPAPIR4 exception

[Scott Klement <rpg400-l@xxxxxxxxxxxxxxxx>]

Read the following two threads from the archives:

http://archive.midrange.com/midrange-l/200605/threads.html#01505
http://archive.midrange.com/midrange-l/200606/threads.html#00087

(actually, it's one thread, but got split into two different months in 
the archives.)


Peter Connell wrote:
> I'm not surprised that Barbara was involved.
> If she has a response at which you can point me, I'd be grateful,
> otherwise I assume that the recommendation is to perform any open on
> explicit descriptors 0,1 and 2 before the JVM starts.
>
> I haven't found anything that will show the number of open file
> descriptors yet (other than in Linux)
>
> I have a feeling that file descriptors may be job related on not subject
> to removal via ending an activation group (as a workaround say)
>
> Peter
>  
>
> -----Original Message-----
> From: rpg400-l-bounces@xxxxxxxxxxxx
> [mailto:rpg400-l-bounces@xxxxxxxxxxxx] On Behalf Of Scott Klement
> Sent: Tuesday, 11 August 2009 8:07 p.m.
> To: RPG programming on the IBM i / System i
> Subject: Re: HTTPAPIR4 exception
>
> Ummm... not sure what the 3 descriptor requirement of Java has to do 
> with HTTPAPIR4??  It sure wouldn't cause the error you're receiving!
>
> But, if you like...  Java expects to have 3 file descriptors open at the
>
> time that the JVM is started.  The 3 descriptors represent stdin, stdout
>
> and stderr, respectively.  On Unix systems, these are always descriptors
>
> 0, 1 and 2.
>
> When ILE RPG starts Java, it doesn't ensure that these descriptors are 
> open.  On other systems like Windows or Unix this is a non-issue, 
> because these descriptors are pretty much always open.  But on i, they 
> are optional, and if you don't have the open and Java tries to use them,
>
> you can have problems.
>
> So some of my Java-related service programs (and I repeat, this does NOT
>
> include HTTPAPI, which uses *no* Java whatsoever) will guarantee that 
> there are at least 3 desriptors open.  That way, Java won't try to use 
> closed descriptors and go haywire.
>
> IF you're looking for more detail than that about why Java needs these, 
> and why *it* (or, at least, RPG) doesn't open them itself, then I won't 
> be able to help you.  I was merely told that Java requires these 
> descriptors, and that it would solve problems if I open them.  The 
> person who told me that (Barbara Morris) didn't fully understand the 
> reason, she just said that it was necessary and that it solved some 
> crashes that people were experiencing with my tools.
>
>
>
> Peter Connell wrote:
> > Thanks,
> > I'd forgotten to check into that.
> > I have a feeling I remember seeing a display that indicated how many
> > descriptors were open but can't recall off the top of my head.
> >
> > BTW, can you comment on your reason for opening the 1st 3 descriptors
> > while commencing a java object group.
> >
> > Peter