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## c++filt

         c++filt [-_|--strip-underscores]
                 [-j|--java]
                 [-n|--no-strip-underscores]
                 [-p|--no-params]
                 [-s format|--format=format]
                 [--help]  [--version]  [symbol...]

The C++ and Java languages provides function overloading, which means that you can write many functions with the same name (providing each takes parameters of different types). All C++ and Java function names are encoded into a low-level assembly label (this process is known as mangling). The `c++filt` 1 program does the inverse mapping: it decodes (demangles) low-level names into user-level names so that the linker can keep these overloaded functions from clashing.

Every alphanumeric word (consisting of letters, digits, underscores, dollars, or periods) seen in the input is a potential label. If the label decodes into a C++ name, the C++ name replaces the low-level name in the output.

You can use `c++filt` to decipher individual symbols:

         c++filt symbol

If no symbol arguments are given, `c++filt` reads symbol names from the standard input and writes the demangled names to the standard output. All results are printed on the standard output.

`-_`
`--strip-underscores`
  On some systems, both the C and C++ compilers put an underscore in front of every name. For example, the C name `foo` gets the low-level name `_foo`. This option removes the initial underscore. Whether `c++filt` removes the underscore by default is target dependent.
`-j`
`--java`
  Prints demangled names using Java syntax. The default is to use C++ syntax.
`-n`
`--no-strip-underscores`
  Do not remove the initial underscore.
`-p`
`--no-params`
  When demangling the name of a function, do not display the types of the function's parameters.
`-s` format
`--format=`format
  `c++filt` can decode various methods of mangling, used by different compilers. The argument to this option selects which method it uses:
  `auto`
    Automatic selection based on executable (the default method)
  `gnu`
    the one used by the GNU C++ compiler (g++)
  `lucid`
    the one used by the Lucid compiler (lcc)
  `arm`
    the one specified by the C++ Annotated Reference Manual
  `hp`
    the one used by the HP compiler (aCC)
  `edg`
    the one used by the EDG compiler
  `gnu-v3`
    the one used by the GNU C++ compiler (g++) with the V3 ABI.
  `java`
    the one used by the GNU Java compiler (gcj)
  `gnat`
    the one used by the GNU Ada compiler (GNAT).
`--help`
  Print a summary of the options to `c++filt` and exit.
`--version`
  Print the version number of `c++filt` and exit.

> Warning: `c++filt` is a new utility, and the details of its user interface are subject to change in future releases. In particular, a command-line option may be required in the the future to decode a name passed as an argument on the command line; in other words,

>               c++filt symbol

> may in a future release become

>               c++filt option symbol

#### Footnotes

1. MS-DOS does not allow `+` characters in file names, so on MS-DOS this program is named `cxxfilt`.