[SCore-users] mpirun STDIN usage with Score

[Atsushi HORI]

Hi.

>Very nice ! Just one more thing that troubles us related to stdin: one of 
>our applications (CHARMM) likes to do rewinds of stdin in order to 
>simulate some loops. This works fine for all non-parallel runs that we've 
>tried, but some parallel environments (SCore included) have problems with 
>it. Will/Could this change in SCore-D change this behaviour too ?

I am happy to know this. What I really need is users' requests.

The CHARMM problem will also be solved in the next release, I think.

In the next SCore release, SCore-D supports "redirection" of STDIN 
and STDOUT. This is very similar to the one found in Unix shell, no I 
should say I implemented the same mechnism. For example,

% scrun a.out =: datfile

will create datfile which contents is the STDOUT of a.out on each 
node. The symbol "=:" is borrowed from Pascal, and is the same as ">" 
in Unix. If you type "=::", then the output is appended. Similary, 
when you do

% scrun a.out := datfile

then the STDIN of a.out is the contents of datfile on each node (not 
the STDIN of scrun).

So, to solve the CHARMM problem, you have to do like the following;

% scrun scatter =: tmpfile :: charmm := tmpfile < charmm.datfile
or 
% scrun scatter -file tmpfile :: charmm := tmpfile < charmm.datfile

The scatter program create a file which is a copy of STDIN of scrun, 
and then CHARMM is invoked with the STDIN of the copied file.

How about this ?

----
Atsushi HORI
Swimmy Software, Inc.