1PATCHELF(1)                      User Manuals                      PATCHELF(1)
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NAME

6       patchelf - Modify ELF files
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SYNOPSIS

10       patchelf OPTION FILE ...
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DESCRIPTION

14       PatchELF is a simple utility for modifying existing ELF executables and
15       libraries.  It can change the dynamic loader ("ELF interpreter") of ex‐
16       ecutables and change the RPATH of executables and libraries.
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OPTIONS

20       The single option given operates on each FILE, editing in place.
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22       Any  option  taking a string argument can also take a file by prefixing
23       the argument with the @ symbol. See EXAMPLES
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26       --page-size SIZE
27              Uses the given page size instead of the default.
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30       --set-interpreter INTERPRETER
31              Change the dynamic  loader  ("ELF  interpreter")  of  executable
32              given to INTERPRETER.
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35       --print-interpreter
36              Prints the ELF interpreter of the executable.
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39       --print-os-abi
40              Prints  the  OS  ABI of the executable (EI_OSABI field of an ELF
41              file).
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44       --set-os-abi ABI
45              Changes the OS ABI of the executable (EI_OSABI field of  an  ELF
46              file).   The  ABI parameter is pretty flexible. For example, you
47              can specify it as a "Linux", "linux",  or  even  "lInUx"  -  all
48              those  names  will  set  EI_OSABI field of the ELF header to the
49              value "3", which corresponds to Linux OS ABI.  The same  applies
50              to other ABI names - System V, FreeBSD, Solaris, etc.
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53       --print-soname
54              Prints  DT_SONAME entry of .dynamic section.  Raises an error if
55              DT_SONAME doesn't exist.
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58       --set-soname SONAME
59              Sets DT_SONAME entry of a library to SONAME.
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62       --set-rpath RUNPATH
63              Change the DT_RUNPATH of the executable or library to RUNPATH.
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66       --add-rpath RUNPATH
67              Add RUNPATH to the existing DT_RUNPATH of the executable or  li‐
68              brary.
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71       --remove-rpath
72              Removes  the  DT_RPATH  or DT_RUNPATH entry of the executable or
73              library.
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76       --shrink-rpath
77              Remove from the DT_RUNPATH or DT_RPATH all directories  that  do
78              not contain a library referenced by DT_NEEDED fields of the exe‐
79              cutable or library.
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81              For instance, if an executable references one library libfoo.so,
82              has an RPATH "/lib:/usr/lib:/foo/lib", and libfoo.so can only be
83              found in /foo/lib, then the new RPATH will be "/foo/lib".
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86       --allowed-rpath-prefixes PREFIXES
87              Combined with the "--shrink-rpath" option, this can be used  for
88              further  rpath  tuning.  For  instance,  if an executable has an
89              RPATH "/tmp/build-foo/.libs:/foo/lib", it is probably  desirable
90              to keep the "/foo/lib" reference instead of the "/tmp" entry.
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93       --print-rpath
94              Prints the DT_RUNPATH or DT_RPATH for an executable or library.
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97       --force-rpath
98              Forces  the  use of the obsolete DT_RPATH in the file instead of
99              DT_RUNPATH. By default DT_RPATH is converted to DT_RUNPATH.
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102       --add-needed LIBRARY
103              Adds a declared dependency on  a  dynamic  library  (DT_NEEDED).
104              This option can be given multiple times.
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107       --replace-needed LIB_ORIG LIB_NEW
108              Replaces a declared dependency on a dynamic library with another
109              one (DT_NEEDED).  This option can be given multiple times.
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112       --remove-needed LIBRARY
113              Removes a declared dependency on LIBRARY (DT_NEEDED entry). This
114              option can be given multiple times.
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117       --print-needed
118              Prints all DT_NEEDED entries of the executable.
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121       --no-default-lib
122              Marks the object so that the search for dependencies of this ob‐
123              ject will ignore any default library search paths.
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126       --no-sort
127              Do not sort program headers or section headers.  This is  useful
128              when  debugging  patchelf,  because  it  makes it easier to read
129              diffs of the output of "readelf -a".
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132       --add-debug-tag
133              Adds DT_DEBUG tag to the .dynamic section if not yet present  in
134              an  ELF  object.  A shared library (-shared) by default does not
135              receive DT_DEBUG tag.  This means that when a shared library has
136              an entry point (so that it can be run as an executable), the de‐
137              bugger does not connect to it correctly and symbols are not  re‐
138              solved.
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141       --output FILE
142              Set  the  output file name.  If not specified, the input will be
143              modified in place.
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146       --debug
147              Prints details of the changes made to the input file.
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150       --version
151              Shows the version of patchelf.
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EXAMPLES

155       To use the contents on an external file as a parameter:
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157              $ patchelf a.out --add-rpath @/tmp/generated-rpath.bin
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159       To change the RPATH of a binary. Note that $ORIGIN is a special  symbol
160       used by the loader, so must be quoted.
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162              patchelf --set-rpath '$ORIGIN/../lib64' a.out
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AUTHOR

167       Eelco Dolstra <e.dolstra@tudelft.nl>
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SEE ALSO

171       elf(5), ld.so(8)
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177PATCHELF                           JULY 2022                       PATCHELF(1)