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]
               [-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]
               [--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.

       --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.

       -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.

       --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.

       --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,  1992,  1993, 1994, 1995, 1996, 1997, 1998, 1999,
       2000, 2001, 2002, 2003, 2004 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-2.15.97                  2005-04-20                        OBJCOPY(1)

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