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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]
	       [-w|--wildcard]
	       [-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]
	       [--redefine-syms=filename]
	       [--weaken]
	       [--keep-symbols=filename]
	       [--strip-symbols=filename]
	       [--keep-global-symbols=filename]
	       [--localize-symbols=filename]
	       [--weaken-symbols=filename]
	       [--alt-machine-code=index]
	       [--prefix-symbols=string]
	       [--prefix-sections=string]
	       [--prefix-alloc-sections=string]
	       [--add-gnu-debuglink=path-to-file]
	       [--only-keep-debug]
	       [--writable-text]
	       [--readonly-text]
	       [--pure]
	       [--impure]
	       [-v|--verbose]
	       [-V|--version]
	       [--help]	[--info]
	       infile [outfile]

DESCRIPTION
       The  GNU	 objcopy  utility  copies  the	contents  of an	object file to
       another.	 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
       expected.

       objcopy creates temporary files to do its translations and deletes them
       afterward.   objcopy  uses  BFD	to do all its translation work;	it has
       access to all the formats described in BFD and thus is able  to	recog-
       nize 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	(e.g., 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
	   option 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 or sections 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.

       -w
       --wildcard
	   Permit  regular  expressions	 in  symbolnames used in other command
	   line	options.  The question mark (?), asterisk (*),	backslash  (\)
	   and square brackets ([]) operators can be used anywhere in the sym-
	   bol name.  If the first character of	the symbol name	is the	excla-
	   mation  point (!) then the sense of the switch is reversed for that
	   symbol.  For	example:

		     -w	-W !foo	-W fo*

	   would cause objcopy to weaken all symbols that  start  with	``fo''
	   except for the symbol ``foo''.

       -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
	   default  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
	   ignores 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
	   default 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
	   extra 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
	   address is the address where	the section will be loaded into	memory
	   at  program	load  time.   Normally	this  is  the  same as the VMA
	   address, 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
	   address  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
	   debug.   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
	   instead.  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
	   binary,  since  this	will always create a section called .data.  If
	   for example,	you wanted instead to create a section called  .rodata
	   containing  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
	   between 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
	   option 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.

       --redefine-syms=filename
	   Apply --redefine-sym	to each	symbol pair "old new"  listed  in  the
	   file	 filename.   filename  is  simply a flat file, with one	symbol
	   pair	per line.  Line	comments may be	introduced by the hash charac-
	   ter.	 This option may be given more than once.

       --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
	   objects  using  the	-R  option to the linker.  This	option is only
	   effective 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
	   indexth  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.

       --writable-text
	   Mark	the output text	as writable.  This option isn't	meaningful for
	   all object file formats.

       --readonly-text
	   Make	the output text	write protected.  This option isn't meaningful
	   for all object file formats.

       --pure
	   Mark	the output file	as demand paged.  This option isn't meaningful
	   for all object file formats.

       --impure
	   Mark	 the  output file as impure.  This option isn't	meaningful for
	   all object file formats.

       --prefix-symbols=string
	   Prefix all symbols in the output file with string.

       --prefix-sections=string
	   Prefix all section names in the output file with string.

       --prefix-alloc-sections=string
	   Prefix all the names	of all allocated sections in the  output  file
	   with	string.

       --add-gnu-debuglink=path-to-file
	   Creates  a  .gnu_debuglink  section	which  contains	a reference to
	   path-to-file	and adds it to the output file.

       --only-keep-debug
	   Strip a file, removing any  sections	 that  would  be  stripped  by
	   --strip-debug and leaving the debugging sections.

	   The	intention is that this option will be used in conjunction with
	   --add-gnu-debuglink	to  create  a  two  part  executable.	One  a
	   stripped  binary  which will	occupy less space in RAM and in	a dis-
	   tribution and the second a debugging	information file which is only
	   needed  if  debugging abilities are required.  The suggested	proce-
	   dure	to create these	files is as follows:

	   1.<Link the executable as normal.  Assuming that is is called>
	       "foo" then...

	   1.<Run "objcopy --only-keep-debug foo foo.dbg" to>
	       create a	file containing	the debugging info.

	   1.<Run "objcopy --strip-debug foo" to create	a>
	       stripped	executable.

	   1.<Run "objcopy --add-gnu-debuglink=foo.dbg foo">
	       to add a	link to	the debugging  info  into  the	stripped  exe-
	       cutable.

	   Note	- the choice of	".dbg" as an extension for the debug info file
	   is arbitrary.  Also the "--only-keep-debug" step is optional.   You
	   could instead do this:

	   1.<Link the executable as normal.>
	   1.<Copy "foo" to  "foo.full">
	   1.<Run "objcopy --strip-debug foo">
	   1.<Run "objcopy --add-gnu-debuglink=foo.full	foo">

	   ie  the  file pointed to by the --add-gnu-debuglink can be the full
	   executable.	It  does  not  have  to	 be  a	file  created  by  the
	   --only-keep-debug switch.

       -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.

       --info
	   Display a list showing all architectures and	object formats	avail-
	   able.

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,
       2003 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''.

binutils-2.14.91		  2004-04-09			    OBJCOPY(1)

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

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