I don't understand your questions. We compile fdisk on every platform, on every type of disk, so I don't understand what WDCC_IDENTIFY has to do with it.
You only care about PCs? > i am reading the fdisk source to have a better understanding > what is what... it is not going really well i am afraid :] > > first of all, i had a long hard look at the basic programs > that give information about disks in general: fdisk, disklabel, > and atactl (obviously, only for ata disks) and /boot. > > both fdisk and disklabel use the DIOCGDINFO ioctl to get the > disk geometry (and other info) but atactl is using the WDCC_IDENTIFY > ata command while /boot is using int 13h. consider the following > output from my eeepc: > > $ sudo fdisk wd0 > Disk: wd0 geometry: 486/255/63 [7815024 Sectors] > <snip> > > $ sudo disklabel wd0 > <snip> > sectors/track: 63 > tracks/cylinder: 255 > sectors/cylinder: 16065 > cylinders: 486 > total sectors: 7815024 > <snip> > > $ sudo atactl wd0 > <snip> > Cylinders: 7753, heads: 16, sec/track: 63, total sectors: 7815024 > <snip> > > the boot output is not here, but it gave me the same numbers > as fdisk. > > so atactl's different (sigh). but the thing is, that if i trace back > what the DIOCGDINFO ioctl does in ata.c and wd.c, ... it is the same > WDCC_IDENTIFY that atactl does... what am i missing here? > > ----------------- > > the other issue i have been pondering is, the user mode -chs in fdisk. > i remember back then when i had this clash of geometries (between say > partition magic, and openbsd) i was inclined to use the partion magic > one... so i had a geometry i wanted to use to override the one openbsd > was giving me. but even if i specified it with -chs, fdisk still used > the one it found. now i see in the source, that the user given geometry > is considered, but only if there is no geometry found by the system, if > the system finds one, it simply overwrites the user defined values. > is this intentional? if the user is brave enough to supply a geometry, > shouldn't it be used over the detected one? > > this would have been useful for me with dual boot when there is already > some other system on the disk installed with using a different geometry. > by entering this "custom" geometry, one will be able to use openbsd's > fdisk with "proper" partition boundaries with a greater chance of not > overwriting already existing partitions. > > if what i am saying is rubbish (more than possible) then at least i > think this should be documented in the man page because basicly the user > suplied -chs values are ignored if there is system geometry present... > > -f > -- > i'm not overweight, i'm undertall! -- garfield
