ld86

ld86(1)								      ld86(1)



NAME
       ld86 - Linker for as86(1)

SYNOPSIS
       ld86  [-03MNdimrstyz[-]]	 [-llib_extension]  [-o outfile]  [-Ccrtfile]
       [-Llibdir]   [-Olibfile]	  [-Ttextaddr]	 [-Hheapsize]	 [-Ddataaddr]
       infile...


DESCRIPTION
       This  linker  understands  only	the object files produced by the as86
       assembler, it can link them into either an impure or  a	separate  I&D
       executable.

       The  linking defaults are everything off or none except for -0 and the
       output file is a.out.   There  is  not  a  standard  library  location
       defined in the linker.


OPTIONS
       -0     produce header with 16-bit magic

       -3     produce header with 32-bit magic

       -d     delete  the  header  from	 the  output file, used for MSDOS COM
	      files. As a side	effect	this  also  includes  -s  as  there’s
	      nowhere to put a symbol table.

       -Cx    add file libdir-from-search/crtx.o to list of files linked

       -D     data base address follows (in format suitable for strtoul)

       -H     the top of heap (initial stack) address (in format suitable for
	      strtoul)

       -Lx    add dir name x to the head of the list of library dirs searched

       -M     print symbols linked on stdout

       -N     Create  a	 native Linux OMAGIC output file. If the contents are
	      i386 code the binary can be either linked by GCC or executed by
	      linux.  If  the  -z  option  is  also  included  the linker can
	      generate a QMAGIC executable.

       -Ox    add library or object  file  libdir-from-search/x	 to  list  of
	      files linked

       -T     text base address follows (in format suitable for strtoul)

       -i     separate I&D output

       -lx    add library libdir-from-search/libx.a to list of files linked

       -m     print modules linked on stdout

       -o     output file name follows

       -s     strip symbols

       -r     Generate	a  relocatable	object from one source object, if the
	      linker is given the -N option also the output  format  will  be
	      the hosts native format if possible.

       -t     trace modules being looked at on stdout

       -y     Alter  the  symbol  tables  to  add  label ’extensions’ so that
	      labels with more than  8	characters  can	 be  stored  in	 elks
	      executables.

       -z     produce "unmapped zero page" or "QMAGIC" executables

       All  the options not taking an argument may be turned off by following
       the option letter by a ’-’, as for cc1.

PREDEFINED LABELS
       The linker predefines several labels that can be	 imported  into	 user
       programs.

       __etext
	      Standard C variable for the end of the text segment.

       __edata
	      Standard C variable for the end of the initilised data.

       __end  Standard C variable for the end of the bss area.

       __segoff
	      The  offset within the executable file between the start of the
	      text segment and the start of  the  data	segment	 in  16	 byte
	      ’paragraphs’.  Note  this	 is  zero  for	impure	(tiny  model)
	      executables and is adjusted for executables that don’t start at
	      offset 0 within the segment.

       __segXDL
	      The  lowest  address  with data in segment ’X’. (eg __seg0DL is
	      for segment zero or the text segment, __seg3DL is for the	 data
	      segment) The value ’X’ is a hex digit.

       __segXDH
	      The top of segment ’X’s data area.

       __segXCL
	      The  bottom  of  segment	’X’s ’common data’ or unitilised data
	      area. Each segment has both an initilised and  unitilised	 data
	      area.

       __segXCH
	      The top of segment ’X’s common area.

       __segXSO
	      This  is	the  adjusted  offset  from segment 0 of the start of
	      segment ’X’ in ’paragraphs’.


HISTORY
       The 6809 version does not support -i.

       The previous versions of the linker could produce an  8086  executable
       with  segments  of  a  size  >64k,  now only i386 executables may have
       segments this large.


BUGS
       The linker cannot deal with reverse seeks caused by  org	 instructions
       in the object file. Unlike previous versions the current one traps the
       error rather than trying to fill up the hard disk.

       The linker produces a broken a.out object file if given one input  and
       the -r option this is so it is compatible with pre-dev86 versions.



				  Apr, 1997			      ld86(1)