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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]
	       [--strip-unneeded-symbol=symbolname]
	       [-G symbolname|--keep-global-symbol=symbolname]
	       [-L symbolname|--localize-symbol=symbolname]
	       [--globalize-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]
	       [--strip-unneeded-symbols=filename]
	       [--keep-global-symbols=filename]
	       [--localize-symbols=filename]
	       [--globalize-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]
	       [--keep-file-symbols]
	       [--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 files 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
	   When  stripping  symbols,  keep  symbol symbolname even if it would
	   normally be stripped.  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.

       --strip-unneeded-symbol=symbolname
	   Do  not  copy  symbol  symbolname from the source file unless it is
	   needed by a relocation.  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.

       --globalize-symbol=symbolname
	   Give symbol symbolname global scoping so that it is visible outside
	   of  the file in which it is defined.  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
	   sections  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  -B  \
		      --rename-section .data=.rodata,alloc,load,readonly,data,contents \
		       

       --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.

       --strip-unneeded-symbols=filename
	   Apply --strip-unneeded-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 charac
	   ter.  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.

       --globalize-symbols=filename
	   Apply  --globalize-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.   For ELF based architectures if the index alternative
	   does not exist then the value is treated as an absolute  number  to
	   be stored in the e_machine field of the ELF header.

       --writable-text
	   Mark the output text as writable.  This option isnt meaningful for
	   all object file formats.

       --readonly-text
	   Make the output text write protected.  This option isnt meaningful
	   for all object file formats.

       --pure
	   Mark the output file as demand paged.  This option isnt meaningful
	   for all object file formats.

       --impure
	   Mark the output file as impure.  This option isnt  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.

       --keep-file-symbols
	   When    stripping   a   file,   perhaps   with   --strip-debug   or
	   --strip-unneeded, retain any symbols specifying source file	names,
	   which would otherwise get stripped.

       --only-keep-debug
	   Strip  a  file, removing contents of any sections that would not be
	   stripped  by  --strip-debug	and  leaving  the  debugging  sections
	   intact.

	   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.
	       "foo" then...

	   1.
	       create a file containing the debugging info.

	   1.
	       stripped executable.

	   1.
	       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.
	   1.
	   1.
	   1.

	   i.e. 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
	   archives, 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.

       @file
	   Read command-line options from file.  The options read are inserted
	   in place of the original @file option.  If file does not exist,  or
	   cannot  be read, then the option will be treated literally, and not
	   removed.

	   Options in file are separated by whitespace.  A whitespace  charac
	   ter	may  be included in an option by surrounding the entire option
	   in either single or double  quotes.	 Any  character  (including  a
	   backslash)  may  be	included  by  prefixing  the  character  to be
	   included with a backslash.  The file may itself contain  additional
	   @file options; any such options will be processed recursively.

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

COPYRIGHT
       Copyright  (c)  1991,  1992,  1993, 1994, 1995, 1996, 1997, 1998, 1999,
       2000, 2001, 2002, 2003, 2004, 2005, 2006 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-2.17			  2006-06-23			    OBJCOPY(1)




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