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OBJCOPY(1)		     GNU Development Tools		    OBJCOPY(1)

NAME
       objcopy - copy and translate object files

SYNOPSIS
       objcopy [-F bfdname|--target=bfdname]
	       [-I bfdname|--input-target=bfdname]
	       [-O bfdname|--output-target=bfdname]
	       [-B bfdarch|--binary-architecture=bfdarch]
	       [-S|--strip-all]	[-g|--strip-debug]
	       [-K symbolname|--keep-symbol=symbolname]
	       [-N symbolname|--strip-symbol=symbolname]
	       [-G symbolname|--keep-global-symbol=symbolname]
	       [-L symbolname|--localize-symbol=symbolname]
	       [-W symbolname|--weaken-symbol=symbolname]
	       [-x|--discard-all] [-X|--discard-locals]
	       [-b byte|--byte=byte]
	       [-i interleave|--interleave=interleave]
	       [-j sectionname|--only-section=sectionname]
	       [-R sectionname|--remove-section=sectionname]
	       [-p|--preserve-dates]
	       [--debugging]
	       [--gap-fill=val]	[--pad-to=address]
	       [--set-start=val] [--adjust-start=incr]
	       [--change-addresses=incr]
	       [--change-section-address section{=,+,-}val]
	       [--change-section-lma section{=,+,-}val]
	       [--change-section-vma section{=,+,-}val]
	       [--change-warnings] [--no-change-warnings]
	       [--set-section-flags section=flags]
	       [--add-section sectionname=filename]
	       [--rename-section oldname=newname[,flags]]
	       [--change-leading-char ]	[--remove-leading-char]
	       [--srec-len=ival	] [--srec-forceS3]
	       [--redefine-sym old=new ]
	       [--weaken]
	       [--keep-symbols=filename]
	       [--strip-symbols=filename]
	       [--keep-global-symbols=filename]
	       [--localize-symbols=filename]
	       [--weaken-symbols=filename]
	       [--alt-machine-code=index]
	       [-v|--verbose]
	       [-V|--version]
	       [--help]
	       infile [outfile]

DESCRIPTION
       The  GNU	 objcopy  utility copies the contents of an object file	to an-
       other.  objcopy uses the	GNU BFD	Library	to read	and write  the	object
       files.	It can write the destination object file in a format different
       from that of the	source object file.  The exact behavior	of objcopy  is
       controlled  by  command-line options.  Note that	objcopy	should be able
       to copy a fully linked file between any two formats. However, copying a
       relocatable  object  file  between  any two formats may not work	as ex-
       pected.

       objcopy creates temporary files to do its translations and deletes them
       afterward.  objcopy uses	BFD to do all its translation work; it has ac-
       cess to all the formats described in BFD	and thus is able to  recognize
       most formats without being told explicitly.

       objcopy	can be used to generate	S-records by using an output target of
       srec (e.g., use -O srec).

       objcopy can be used to generate a raw binary file by  using  an	output
       target  of  binary (e.g., use -O	binary).  When objcopy generates a raw
       binary file, it will essentially	produce	a memory dump of the  contents
       of  the input object file.  All symbols and relocation information will
       be discarded.  The memory dump will start at the	load  address  of  the
       lowest section copied into the output file.

       When  generating	an S-record or a raw binary file, it may be helpful to
       use -S to remove	sections containing debugging  information.   In  some
       cases  -R  will	be useful to remove sections which contain information
       that is not needed by the binary	file.

       Note - objcopy is not able to change the	endianness of its input	files.
       If  the	input format has an endianness,	(some formats do not), objcopy
       can only	copy the inputs	into file formats that have the	 same  endian-
       ness or which have no endianness	(eg srec).

OPTIONS
       infile
       outfile
	   The	input  and  output files, respectively.	 If you	do not specify
	   outfile, objcopy creates a temporary	file and destructively renames
	   the result with the name of infile.

       -I bfdname
       --input-target=bfdname
	   Consider the	source file's object format to be bfdname, rather than
	   attempting to deduce	it.

       -O bfdname
       --output-target=bfdname
	   Write the output file using the object format bfdname.

       -F bfdname
       --target=bfdname
	   Use bfdname as the object format for	both the input and the	output
	   file; i.e., simply transfer data from source	to destination with no
	   translation.

       -B bfdarch
       --binary-architecture=bfdarch
	   Useful when transforming a raw binary input	file  into  an	object
	   file.   In this case	the output architecture	can be set to bfdarch.
	   This	option will be ignored if the input file has a known  bfdarch.
	   You can access this binary data inside a program by referencing the
	   special symbols that	are created by the conversion process.	 These
	   symbols  are	 called	_binary_objfile_start, _binary_objfile_end and
	   _binary_objfile_size.  e.g. you can transform a picture  file  into
	   an object file and then access it in	your code using	these symbols.

       -j sectionname
       --only-section=sectionname
	   Copy	only the named section from the	input file to the output file.
	   This	option may be given more than once.  Note that using this  op-
	   tion	inappropriately	may make the output file unusable.

       -R sectionname
       --remove-section=sectionname
	   Remove  any	section	 named sectionname from	the output file.  This
	   option may be given more than once.	Note that  using  this	option
	   inappropriately may make the	output file unusable.

       -S
       --strip-all
	   Do not copy relocation and symbol information from the source file.

       -g
       --strip-debug
	   Do not copy debugging symbols from the source file.

       --strip-unneeded
	   Strip all symbols that are not needed for relocation	processing.

       -K symbolname
       --keep-symbol=symbolname
	   Copy	 only symbol symbolname	from the source	file.  This option may
	   be given more than once.

       -N symbolname
       --strip-symbol=symbolname
	   Do not copy symbol symbolname from the source  file.	  This	option
	   may be given	more than once.

       -G symbolname
       --keep-global-symbol=symbolname
	   Keep	 only  symbol symbolname global.  Make all other symbols local
	   to the file,	so that	they are not visible externally.  This	option
	   may be given	more than once.

       -L symbolname
       --localize-symbol=symbolname
	   Make	symbol symbolname local	to the file, so	that it	is not visible
	   externally.	This option may	be given more than once.

       -W symbolname
       --weaken-symbol=symbolname
	   Make	symbol symbolname weak.	This option may	 be  given  more  than
	   once.

       -x
       --discard-all
	   Do not copy non-global symbols from the source file.

       -X
       --discard-locals
	   Do not copy compiler-generated local	symbols.  (These usually start
	   with	L or ..)

       -b byte
       --byte=byte
	   Keep	only every byteth byte of the input file (header data  is  not
	   affected).	byte can be in the range from 0	to interleave-1, where
	   interleave is given by the -i or --interleave option,  or  the  de-
	   fault  of  4.   This	option is useful for creating files to program
	   ROM.	 It is typically used with an "srec" output target.

       -i interleave
       --interleave=interleave
	   Only	copy one out of	every interleave bytes.	 Select	which byte  to
	   copy	 with the -b or	--byte option.	The default is 4.  objcopy ig-
	   nores this option if	you do not specify either -b or	--byte.

       -p
       --preserve-dates
	   Set the access and modification dates of the	output file to be  the
	   same	as those of the	input file.

       --debugging
	   Convert  debugging  information,  if	possible.  This	is not the de-
	   fault because only certain debugging	formats	are supported, and the
	   conversion process can be time consuming.

       --gap-fill val
	   Fill	gaps between sections with val.	 This operation	applies	to the
	   load	address	(LMA) of the sections.	It is done by  increasing  the
	   size	 of the	section	with the lower address,	and filling in the ex-
	   tra space created with val.

       --pad-to	address
	   Pad the output file up to the load address address.	This  is  done
	   by  increasing  the	size  of the last section.  The	extra space is
	   filled in with the value specified by --gap-fill (default zero).

       --set-start val
	   Set the start address of the	new file to val.  Not all object  file
	   formats support setting the start address.

       --change-start incr
       --adjust-start incr
	   Change  the start address by	adding incr.  Not all object file for-
	   mats	support	setting	the start address.

       --change-addresses incr
       --adjust-vma incr
	   Change the VMA and LMA addresses of all sections, as	 well  as  the
	   start  address,  by	adding	incr.  Some object file	formats	do not
	   permit section addresses to be changed arbitrarily.	Note that this
	   does	 not relocate the sections; if the program expects sections to
	   be loaded at	a certain address, and this option is used  to	change
	   the	sections such that they	are loaded at a	different address, the
	   program may fail.

       --change-section-address	section{=,+,-}val
       --adjust-section-vma section{=,+,-}val
	   Set or change both the VMA address and the LMA address of the named
	   section.   If = is used, the	section	address	is set to val.	Other-
	   wise, val is	added to or subtracted from the	section	address.   See
	   the	comments  under	--change-addresses, above. If section does not
	   exist  in  the  input  file,	 a  warning  will  be  issued,	unless
	   --no-change-warnings	is used.

       --change-section-lma section{=,+,-}val
	   Set	or  change  the	LMA address of the named section.  The LMA ad-
	   dress is the	address	where the section will be loaded  into	memory
	   at  program	load  time.   Normally this is the same	as the VMA ad-
	   dress, which	is the address of the section at program run time, but
	   on  some  systems, especially those where a program is held in ROM,
	   the two can be different.  If = is used, the	section	address	is set
	   to  val.  Otherwise,	val is added to	or subtracted from the section
	   address.  See the comments  under  --change-addresses,  above.   If
	   section does	not exist in the input file, a warning will be issued,
	   unless --no-change-warnings is used.

       --change-section-vma section{=,+,-}val
	   Set or change the VMA address of the	named section.	 The  VMA  ad-
	   dress  is  the  address  where the section will be located once the
	   program has started executing.  Normally this is the	 same  as  the
	   LMA	address, which is the address where the	section	will be	loaded
	   into	memory,	but on some systems, especially	those where a  program
	   is  held  in	ROM, the two can be different.	If = is	used, the sec-
	   tion	address	is set to val.	Otherwise, val is  added  to  or  sub-
	   tracted   from   the	 section  address.   See  the  comments	 under
	   --change-addresses, above.  If section does not exist in the	 input
	   file,  a  warning  will  be	issued,	unless --no-change-warnings is
	   used.

       --change-warnings
       --adjust-warnings
	   If	 --change-section-address    or	   --change-section-lma	    or
	   --change-section-vma	is used, and the named section does not	exist,
	   issue a warning.  This is the default.

       --no-change-warnings
       --no-adjust-warnings
	   Do not issue	a warning if --change-section-address or --adjust-sec-
	   tion-lma or --adjust-section-vma is used, even if the named section
	   does	not exist.

       --set-section-flags section=flags
	   Set the flags for the named section.	 The flags argument is a comma
	   separated  string  of  flag names.  The recognized names are	alloc,
	   contents, load, noload, readonly, code, data, rom, share,  and  de-
	   bug.	  You  can  set	the contents flag for a	section	which does not
	   have	contents, but it is not	meaningful to clear the	contents  flag
	   of  a section which does have contents--just	remove the section in-
	   stead.  Not all flags are meaningful	for all	object file formats.

       --add-section sectionname=filename
	   Add a new section named sectionname while copying  the  file.   The
	   contents  of	the new	section	are taken from the file	filename.  The
	   size	of the section will be the size	of the file.  This option only
	   works  on  file  formats  which can support sections	with arbitrary
	   names.

       --rename-section	oldname=newname[,flags]
	   Rename a section from oldname to newname, optionally	 changing  the
	   section's  flags  to	 flags in the process.	This has the advantage
	   over	usng a linker script to	perform	the rename in that the	output
	   stays as an object file and does not	become a linked	executable.

	   This	 option	 is  particularly helpful when the input format	is bi-
	   nary, since this will always	create a section called	.data.	If for
	   example, you	wanted instead to create a section called .rodata con-
	   taining binary data you could use the  following  command  line  to
	   achieve it:

		     objcopy -I	binary -O <output_format> -B <architecture> \
		      --rename-section .data=.rodata,alloc,load,readonly,data,contents \
		      <input_binary_file> <output_object_file>

       --change-leading-char
	   Some	 object	 file  formats	use special characters at the start of
	   symbols.  The most common such character is underscore, which  com-
	   pilers often	add before every symbol.  This option tells objcopy to
	   change the leading character	of every symbol	when it	 converts  be-
	   tween object	file formats.  If the object file formats use the same
	   leading character, this option has no effect.  Otherwise,  it  will
	   add	a  character, or remove	a character, or	change a character, as
	   appropriate.

       --remove-leading-char
	   If the first	character of a global symbol is	a special symbol lead-
	   ing character used by the object file format, remove	the character.
	   The most common symbol leading character is underscore.   This  op-
	   tion	 will  remove  a  leading  underscore from all global symbols.
	   This	can be useful if you want to link together objects of  differ-
	   ent file formats with different conventions for symbol names.  This
	   is different	from --change-leading-char because it  always  changes
	   the	symbol	name  when  appropriate, regardless of the object file
	   format of the output	file.

       --srec-len=ival
	   Meaningful only for srec output.  Set the  maximum  length  of  the
	   Srecords  being produced to ival.  This length covers both address,
	   data	and crc	fields.

       --srec-forceS3
	   Meaningful  only  for  srec	output.	  Avoid	 generation  of	 S1/S2
	   records, creating S3-only record format.

       --redefine-sym old=new
	   Change  the	name of	a symbol old, to new.  This can	be useful when
	   one is trying link two  things  together  for  which	 you  have  no
	   source, and there are name collisions.

       --weaken
	   Change all global symbols in	the file to be weak.  This can be use-
	   ful when building an	object which will be linked against other  ob-
	   jects  using	 the -R	option to the linker.  This option is only ef-
	   fective when	using an object	file format which supports  weak  sym-
	   bols.

       --keep-symbols=filename
	   Apply  --keep-symbol	option to each symbol listed in	the file file-
	   name.  filename is simply a flat file, with	one  symbol  name  per
	   line.  Line comments	may be introduced by the hash character.  This
	   option may be given more than once.

       --strip-symbols=filename
	   Apply --strip-symbol	option to each symbol listed in	the file file-
	   name.   filename  is	 simply	 a flat	file, with one symbol name per
	   line.  Line comments	may be introduced by the hash character.  This
	   option may be given more than once.

       --keep-global-symbols=filename
	   Apply --keep-global-symbol option to	each symbol listed in the file
	   filename.  filename is simply a flat	file, with one symbol name per
	   line.  Line comments	may be introduced by the hash character.  This
	   option may be given more than once.

       --localize-symbols=filename
	   Apply --localize-symbol option to each symbol listed	 in  the  file
	   filename.  filename is simply a flat	file, with one symbol name per
	   line.  Line comments	may be introduced by the hash character.  This
	   option may be given more than once.

       --weaken-symbols=filename
	   Apply  --weaken-symbol  option  to  each  symbol listed in the file
	   filename.  filename is simply a flat	file, with one symbol name per
	   line.  Line comments	may be introduced by the hash character.  This
	   option may be given more than once.

       --alt-machine-code=index
	   If the output architecture has alternate machine codes, use the in-
	   dexth  code	instead	 of the	default	one.  This is useful in	case a
	   machine is assigned an official code	and the	tool-chain adopts  the
	   new	code, but other	applications still depend on the original code
	   being used.

       -V
       --version
	   Show	the version number of objcopy.

       -v
       --verbose
	   Verbose output: list	all object files modified.  In the case	of ar-
	   chives, objcopy -V lists all	members	of the archive.

       --help
	   Show	a summary of the options to objcopy.

SEE ALSO
       ld(1), objdump(1), and the Info entries for binutils.

COPYRIGHT
       Copyright  (c)  1991,  92, 93, 94, 95, 96, 97, 98, 99, 2000, 2001, 2002
       Free Software Foundation, Inc.

       Permission is granted to	copy, distribute and/or	modify	this  document
       under  the  terms of the	GNU Free Documentation License,	Version	1.1 or
       any later version published by the Free Software	 Foundation;  with  no
       Invariant  Sections,  with no Front-Cover Texts,	and with no Back-Cover
       Texts.  A copy of the license is	included in the	section	entitled  "GNU
       Free Documentation License".

3rd Berkeley Distribution	  2002-08-05			    OBJCOPY(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | SEE ALSO | COPYRIGHT

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