X-Authentication-Warning:	delorie.com: mail set sender to djgpp-bounces using -f
From:	Rod Pemberton <NeedNotReplyHere AT xrsevnneqk DOT cem>
Newsgroups:	comp.os.msdos.programmer,comp.os.msdos.djgpp
Subject:	Re: linker error segment_text exceeds 64k in c
Date:	Fri, 23 Jun 2017 20:49:18 -0400
Organization:	Aioe.org NNTP Server
Lines:	43
Message-ID:	<oikcs5$uju$1@gioia.aioe.org>
References:	<32f75ea1-2f4b-476e-a524-661bbae40ad5 AT googlegroups DOT com>
	<2c82f868-3721-4749-9439-159b91d3767a AT googlegroups DOT com>
	<0aeb15e6-767a-443b-ba24-a1c22191db02 AT googlegroups DOT com>
	<144gqr6md2lo5 DOT 1oia572hfg8dg DOT dlg AT 40tude DOT net>
	<oijkp8$1qjn$1 AT gioia DOT aioe DOT org>
NNTP-Posting-Host:	ZTD62cW/Uw8bymX5ok+0NA.user.gioia.aioe.org
Mime-Version:	1.0
X-Complaints-To:	abuse AT aioe DOT org
X-Notice:	Filtered by postfilter v. 0.8.2
Bytes:	2890
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp
Reply-To:	djgpp AT delorie DOT com

On Fri, 23 Jun 2017 17:56:56 +0000 (UTC)
rridge AT csclub DOT uwaterloo DOT ca (Ross Ridge) wrote:

> JJ  <jj4public AT vfemail DOT net> wrote:

(Added, comp.os.msdos.djgpp. in case someone wants to criticize.)

> >Does that mean that DJGPP's C/C++ compiler only have one large
> >memory model?  
> 
> DJGPP has only the 32-bit "flat" memory model.  It's like the tiny
> memory model except the size of its one segment is 4 gigabytes instead
> of 64 kilobytes.
> 

Actually, by default, DJGPP segments are limited to 640KB (0x0009FFFF)
in size for CS, DS, ES and SS, but not FS and GS.  So, you must call
__djgpp_nearptr_enable() to enable 4GB segments.  That will boost the
limit of those four segments to 0xFFFFFFFF.  FS will still be limited
to 64KB and GS will still be limited to 1MB+64KB.  The base for the
four main segments is 1MB, not zero.  GS' base is zero.  FS' base
varies, usually around 0x7C00.  This is true for all 3 compatible DPMI
hosts: CWSDPMI, CWSDPR0, and PMODEDJ.  You can change the base and
privileges of the selectors using other calls.

CS (code segment) is used by _my_cs() and _go32_my_cs().  DS (data
segment) is used by _my_ds() and _go32_my_ds().  SS (stack segment) is
used for _my_ss() and _go32_my_ss().  ES (extra segment) is used for
the PSP selector.  GS is used for __djgpp_dos_sel, _dos_ds,
_go32_info_block.selector_for_linear_memory,
_go32_conventional_mem_selector().  GS is used by libc for the segment
1MB+64KB, e.g., for real-mode DOS or BIOS or VGA routines.
__djgpp_ds_alias mirrors DS' settings and is used for RMCB's.  FS is
used for far pointers (farpeek, farpoke).


Rod Pemberton

-- 
The entire idea that the U.S. government obtained information from deep
sources in the Russian government that Putin ordered a cyber campaign
to disrupt our democracy is itself dezinformatsiya.  Wake up sheeple.

- Raw text -