Le jeudi 18 septembre 2003 � 14:20:52, Damien Sauveron a �crit:
> Hi,

Hello,

> - Search if an other reader using the same ifdhandler exist.
> - if yes ask to the ifdhandler of the first reader connected to PC/SC if 
> it supports multiple channels (IFDHGetCapabilities with the tag 
> TAG_IFD_SIMULTANEOUS_ACCESS)
> 
> Here, there is a problem of this process due to the mutex on calls to 
> the functions regarding the first reader. Indeed imagine that the first 
> reader has send a command to a smart card and that the process on the 
> smart card spend a long time (this call have set the mutex). If the 
> second reader is plugged in this laps because the mutex is set, on the 
> call IFDHGetCapabilities it must wait a long time that the mutex is 
> unset. After many time it will be completly detected by PC/SC.

Why would you need to protect IFDHGetCapabilities() by a mutex?
This function does only give information without changing anything in
the driver.

The only places I see a use for mutex is in IFDHCreateChannel() and
IFDHCloseChannel() since they change the state of available readers.
All the other functions have a read only access on shared data (shared
by all the readers the driver manages) and read/write access to private
data only.

A multi-slot reader may be different but I have not yet seen such a
beast.

Please correct me if I'm wrong.

-- 
 Dr. Ludovic Rousseau                        [EMAIL PROTECTED]
 -- Normaliser Unix c'est comme pasteuriser le camembert, L.R. --
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