* Original Area: Netmail
* Original To  : Norbert Heller (2:246/1409.4)


 NH> how can i here figure out the amount (bytes) of data 
 NH> actually read from the cd rom ? 
 NH> sizeof(buf) results to 6000, but the programming 
 NH> guides specify a longsector with 2048bytes + some ecc 
 NH> code 
 NH> from the logic, with each of the above DosDevIOCtl 
 NH> statements reads around 2350 bytes of data, is that 
 NH> correct? 


You have to know the type of data you are reading ("Red Book",
"Yellow Book", etc) -- I have a generic book on cdrom's (has
nothing to do with os/2) that talks about it.

A cd audio disk (CD-DA) has a sector size of 2352 bytes;  this includes all
of the ecc data (I think) -- regardless,  you send the whole thing to the
sound card -- it worries about everything else.

See /ddkx86/src/dev/dasd/cdrom/os2cdrom/cdioctl.h (from the ddk devcon
cdrom) for some #define's.


--- Maximus/2 3.00