The Question is:
I read the wiz_4064 about $getdvi DEVCLASS and DEVTYPE codes... My question is
when you search the $DCDEF and have multiple returns, how do you distinguish
the correct one. Is there a more generic way to do this in C with the system
I did f$getdvi("EWA0:","DEVTYPE") which returned 68.
The search returns
$EQU DT$_RZ57I 68
$EQU DT$_TZ875 68
$EQU DT$_DZ730 68
$EQU DT$_EW_DE435 68
Show Device obviously knows since I get :
$ show device/full ewa0:
Device EWA0:, device type DE435, is online, network device, device is a template
Error count 0 Operations completed 0
Owner process "" Owner UIC [SYSTEM]
Owner process ID 00000000 Dev Prot S:RWPL,O:RWPL,G,W
Reference count 0 Default buffer size 512
The Answer is :
Device type and device class operate in conjunction, with the type
codes being specific to a class. These codes are typically valid
only for older devices and for devices that have required explicit
OpenVMS changes for support.
That said, identification of the device should typically be
made via DCL such as:
$ sho sym x
X = "RZ29B"
$ sho sym x
X = "DE435"
Or via the associated sys$getdvi and sys$getdviw system services.