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High Level PENs

   

The high level PEN callback functions allows you to install a specific callback function for each class of PEN (see section 7 for a detailed description). The low level interface is used for building this, e.g. by using the low level interface to PEN you will effectively disable the high level interface. In normal cases the high level interface will be sufficient. We have the following different high level event:

The call format of the callback function is:

(*callback)(void *extra, int index, char *msg);

where the argument have the following declaration and content:

The function returns the previous callback function, if any.



Martin Sjolin
Thu Jun 15 20:41:59 MET DST 1995