In article <20151023214718.cd1b12e...@panix3.panix.com>, Stephen Fisher <sfis...@panix.com> wrote: >While learning how to write assembly code on NetBSD, I decided to extend >readelf.c (from GNU binutils) to show the NT_VERSION value in an ELF >header, which is the NetBSD version in the format of the >__NetBSD_Version__ macro from sys/param.h. The value comes out as a 32-bit >integer: for example 601000500 for 6.1.5. How do I handle that value >in a C program? If I follow the logic of the __NetBSD_Prereq__ macro, >only the first digit of each field (MMmmrrpp major/minor/0/patch level) can >be used so major version 6 is represented as 60. What if it goes to 10 or >higher? While researching the source code for this issue, I found out that >the file utility in src/external/bsd/file/dist/src/readelf.c handles it the old >way still: > > * M = major version > * m = minor version > * r = release ["",A-Z,Z[A-Z] but numeric] > * p = patchlevel > >...which I understand was depreciated in 2004, so if I fake the value 99 for >minor version (to indicate current) in the assembler section note, the file >command shows "...for NetBSD 6.9ZZZL...". If I put in a major version 10 >in the assembly source, then my current binutils readelf.c changes (based on >the prereq macro's logic) shows version 1 instad of 10.
$ readelf -n /bin/ls Notes at offset 0x000001dc with length 0x00000018: Owner Data size Description NetBSD 0x00000004 IDENT 799000400 (7.99.4) Notes at offset 0x000001f4 with length 0x00000014: Owner Data size Description NetBSD 0x00000004 PaX <> $ readelf -v GNU readelf (NetBSD Binutils nb1) 2.23.2 Copyright 2012 Free Software Foundation, Inc. This program is free software; you may redistribute it under the terms of the GNU General Public License version 3 or (at your option) any later version. This program has absolutely no warranty. christos
