car@trux.UUCP (Chris Rende) (06/12/90)
In article <2620@ditsyda.oz>, evans@ditsyda.oz (Bruce.Evans) writes: > In article <24725@usc.edu> kjh@pollux.usc.edu (Kenneth J. Hendrickson) writes: > >Is it better to have /dev filled up with every possible device that a > >machine can have, just in case you want to use it in the future, or > >would it be better to have /dev filled with only the actual devices you > >really have on your system? I can see advantages to both. What is done > >on bigger *nix platforms? Why? I've been wondering about this too lately... > On a bigger system, they all have to be there, so the users don't have to > bother the system administrator at 4am. There are 430 entries in /dev on > the BSD system I'm logged onto now. My system here at work has 1188 entries in /dev. I'd say that 80% of them could be removed because they refer to devices which I don't have or use. I've been considering writing them to tape (with CPIO) and removing them. They slow things down when doing directory operations like 'ls /dev/t*'. > On Minix, the devices have to be there, or a program to create them and/or > documentation must be kept around. I find the most convenient documentation > of device numbers is "ls -l /dev". I agree. I found out the hard way about not having all of /dev/hd[0123456789] on my root file system floppy disk: While upgrading I had one file system on hd6 and another file system on hd2. In the process of upgrading I copied the filesystem from hd6 to hd2 and then destroyed the hd6 copy (after all, I had a good copy on hd2 - write?). However, when I booted my new version of Minix with the old /dev entries I found that I had removed /dev/hd2 because I wasn't using it. The end result was that I couldn't mount hd2 on the new version of Minix (and, of course, mknod was on hd2). The details are a bit foggy, but the right idea is there... Now, I'm going to keep /dev entries for all HD and FD devices. However, for partitions which I'm not using, I'm going to use capital letters. I.e., /dev/HD3. car. -- Christopher A. Rende Central Cartage (Nixdorf/Pyramid/SysVR2/BSD4.3) uunet!edsews!rphroy!trux!car Multics,DTSS,Unix,Shortwave,Scanners,StarTrek trux!car@uunet.uu.net Minix 1.2,PC/XT,Mac+,TRS-80 Model I,1802 ELF "I don't ever remember forgetting anything." - Chris Rende
V2057A%TEMPLEVM.BITNET@cornellc.cit.cornell.edu (Juan Jose Noyles) (06/14/90)
I was a bit confused when this topic first began circulating, but I understand now (I think). MINIX doesn't actually NEED all of those special files, but you can't use them if they don't exist. UNIX is the same way.