Hi

> > Not sure how the rest of you specify mhttpd to work with multiple experiments on
> > one machine, but it would seem not the same as me ;-)
> 
> Please note that there has been a change concerning multiple experiments inside 
> mhttpd. From revision 4346 on, mhttpd can only connect to one single experiment, 
> and the experiment name in the URL (aka ?exp=name) is not supported any more. So if 
> you have several experiments, you start several instances of mhttpd now on 
> different ports.

That i do with : 
mhttpd -p xx -e experiment_name -D

> 
> > that experiment name is not transfered to transitions as cm_transition never
> > specifies the experiment in the call to "transition STOP" etc.
> > the only flag it sends is a -d for debug if selected.
> 
> When connecting to an experiment, any midas client uses the ODB from that 
> experiment so lives in that "namespace". So one client can never call any client 
> from another experiment. So your problem must be something else. Of course there is 
> not parameter "experiment" passed to cm_transition() since the experiment is 
> implicitly defined by the ODB mhttpd is attached to.

Will have to look else where.

> 
> > The result is that the stop and start button of the webinterface does not work,
> > and transitions sit endlessly doing nothing but consuming all the processor,
> > odbedit works fine though.
> 
> I guess you have to do some debugging there. Note that "detached" transitions have 
> been implemented recently by Konstantin, so maybe your problem is related to that. 
> In this case Konstantin should check what's wrong.

cm_transition does a "system(str)" on line 3243 inside the "if(async_flag == DETACH)" of
line 3219, how does an external program know about the state of the originating mhttpd
process ? Surely that str which executes "mtransition ......." should get a -e
specifying the experiment explicitly ? probably a -h as well to be thorough.
The only other way that mtransition.cxx will be able to pull in the experimentname is
from the environment variable in its call to cm_get_environment(....) on its startup.


Ok after some testing .... 
If i start the mhttpd with the environment variable MIDAS_EXPT_NAME set then its happy
as mtransition inherits the environment of mhttpd so cm_get_environment(...) of
mtransition picks up the experiment. Similarly if i insert "-e experimentname" into the
string "str" that is passed in system(str) of line 3243. Then start and stop buttons work. 

Konstantin any comments.

I suppose i can live with starting mhttpd with the environment set before running, but
that kind of negates the command line argument to mhttpd. 

Thanks for the help

Sean