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Xref: sserve comp.unix.wizards:30146 comp.unix.questions:36884 comp.unix.bsd:12317 Path: sserve!newshost.anu.edu.au!munnari.oz.au!news.Hawaii.Edu!ames!agate!soda.berkeley.edu!scott From: scott@soda.berkeley.edu (Scott Silvey) Newsgroups: comp.unix.wizards,comp.unix.questions,comp.unix.bsd Subject: BSD filesystem and od utility Date: 22 Jul 1993 21:51:05 GMT Organization: U.C. Berkeley, CS Undergraduate Association Lines: 54 Distribution: world Message-ID: <22n249$2fv@agate.berkeley.edu> NNTP-Posting-Host: soda.berkeley.edu Hello all! For those of you out there who are familiar with the 'od' utility and directory content of a BSD filesystem, I have a few questions for you. Please note that the data below was produced on a BSD 4.3 machine. When I use "od -cdw12 ~" I get the following (which is, of course, not the complete listing) 0000000 \0 \0 016 \0 \0 \f \0 001 . \0 \0 \0 00000 03584 00012 00001 11776 00000 0000014 \0 \0 007 \0 \0 \f \0 002 . . \0 \0 00000 01792 00012 00002 11822 00000 0000030 \0 \0 016 001 \0 024 \0 013 . X r e 00000 03585 00020 00011 11864 29285 0000044 s o u r c e s \0 \0 \0 016 002 29551 30066 25445 29440 00000 03586 0000060 \0 020 \0 006 . a l i a s \0 \0 00016 00006 11873 27753 24947 00000 0000074 \0 \0 016 003 \0 020 \0 006 . c s h 00000 03587 00016 00006 11875 29544 0000110 r c \0 \0 \0 \0 016 004 \0 020 \0 004 29283 00000 00000 03588 00016 00004 0000124 . e n v \0 \0 \0 \0 \0 \0 016 005 11877 28278 00000 00000 00000 03589 My questions are as follows: 1) [looking at the row starting at offset 0]: what does the '016' entry mean? This entry is also found as a delimeter in the other file entries as well. I have also observed that different users on a system usually have a different delimeter than '016' (I have also seen 'M', 'T', '020', etc... used). Why/What is this? I realize that '3584' is an inode entry and '001' is a file length, but what is the '11776' entry in the second row? 2) Why is the data in the second row of each offset put into groups of 5 bytes each? These groupings also appear to have a correlation to the data of line 1 of each offset (a form feed '\f', is indeed an ascii '012'), but what is it? Any information would be greatly appreciated. Thanx in advance, Jon. P.S. Please mail replies/clarifications to 'jon@lurnix.com' - I don't get to read news very often and this will insure I get your reply.