Q: How can I obtain an Ethernet address programmatically? I can get correct
Ethernet addresses for RAM-based drivers, but this does not appear to work for
all drivers. For example, addresses for PowerBooks with DaynaPort connections
are not available. I am using the following code to obtain Ethernet addresses:
myErr = OpenDriver("\p.ENET", &myRefNum);
theEPB.EParms1.ioRefNum = myRefNum;
theEPB.EParms1.ePointer = NewPtrClear(78);
theEPB.EParms1.eBuffSize = 78;
theEPB.EParms1.ioNamePtr = NULL;
myErr = EGetInfo(&theEPB,false);
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How can I scan through all the installed Ethernet drivers for the one that's active
and obtain information about that one?
A: Your approach for obtaining Ethernet address information seems appropriate.
Here are a few pieces of information that may help:
- OpenDriver("\p.ENET", &myRefNum) only opens the first Ethernet driver. If the system has more than one Ethernet card installed, you have to open them explicitly.
- Machines such as the SE and PowerBooks that have the Ethernet hardware connected via the SCSI port are accessed through ENET0 (most machines have this ability).
The following is a code fragment that you can use:
/* check internal non slotted card
check if enet0 driver is installed
*/
short saveRes;
saveRes = LMGetResLoad();
LMSetResLoad(0)
GetNamedResource('DRVR',"\p.ENET0"); // check if ENET0 is in ROM
LMSetResLoad(saveRes)
if(!ResError()) {
/* Setup Open PB */
PB.slotDevParam.ioNamePtr = "\p.ENET0"; // Attempt to open it
PB.slotDevParam.ioVRefNum = 0;
PB.slotDevParam.csCode = 0;
PB.slotDevParam.ioSlot = 0;
PB.slotDevParam.ioID = 0;
/* try and open the internal non slotted enet card */
ErrNo = PBOpenSync(&PB); // notice I do a regular open call $A000
refnum = PB.ioRefNum;
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- For NuBus and SE30 devices (and PCI slots), you have to use the Slot Manager to scan for available Ethernet cards, per this example:
/* Setup Open PB for sloted device */
PB.slotDevParam.ioNamePtr = "\p.ENET";
PB.slotDevParam.ioVRefNum = 0;
PB.slotDevParam.csCode = 0;
/* try Slotmanger Call */
if(!OSTrapAvailable (_SlotManager)) return(Error);
SPB.spExtDev = 0;
SPB.spCategory = 4; /* Network */
SPB.spCType = 1 ; /* EtherNet */
SPB.spTBMask = 0x3;
/* loop on each card */
while((ErrNo = SNextTypeSRsrc(&SPB)) == noErr){
PB.slotDevParam.ioSlot = SPB.spSlot;
PB.slotDevParam.ioID = SPB.spID;
/* try and open the enet card */
ErrNo = PBOpenImmed(&PB); // Notice I Do an OpenImmed $A200
refnum = PB.ioRefNum;
}
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- An important point to consider:
OpenDriver calls fail when Ethernet devices are not cabled or hooked up, so it's not possible to get the address of Ethernet cards that aren't hooked up.
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