Iconv

Section: User Contributed Perl Documentation (3pm)
Updated: 2018-11-03
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NAME

Text::Iconv - Perl interface to iconv() codeset conversion function

SYNOPSIS

  use Text::Iconv;
  $converter = Text::Iconv->new("fromcode", "tocode");
  $converted = $converter->convert("Text to convert");

DESCRIPTION

The Text::Iconv module provides a Perl interface to the iconv() function as defined by the Single UNIX Specification.

The convert() method converts the encoding of characters in the input string from the fromcode codeset to the tocode codeset, and returns the result.

Settings of fromcode and tocode and their permitted combinations are implementation-dependent. Valid values are specified in the system documentation; the iconv(1) utility should also provide a -l option that lists all supported codesets.

Utility methods

Text::Iconv objects also provide the following methods:

retval() returns the return value of the underlying iconv() function for the last conversion; according to the Single UNIX Specification, this value indicates ``the number of non-identical conversions performed.'' Note, however, that iconv implementations vary widely in the interpretation of this specification.

This method can be called after calling convert(), e.g.:

  $result = $converter->convert("lorem ipsum dolor sit amet");
  $retval = $converter->retval;

When called before the first call to convert(), or if an error occured during the conversion, retval() returns undef.

get_attr(): This method is only available with GNU libiconv, otherwise it throws an exception. The get_attr() method allows you to query various attributes which influence the behavior of convert(). The currently supported attributes are trivialp, transliterate, and discard_ilseq, e.g.:

  $state = $converter->get_attr("transliterate");

See iconvctl(3) for details. To ensure portability to other iconv implementations you should first check for the availability of this method using eval {}, e.g.:

    eval { $conv->get_attr("trivialp") };
    if ($@)
    {
      # get_attr() is not available
    }
    else
    {
      # get_attr() is available
    }

This method should be considered experimental.

set_attr(): This method is only available with GNU libiconv, otherwise it throws an exception. The set_attr() method allows you to set various attributes which influence the behavior of convert(). The currently supported attributes are transliterate and discard_ilseq, e.g.:

  $state = $converter->set_attr("transliterate");

See iconvctl(3) for details. To ensure portability to other iconv implementations you should first check for the availability of this method using eval {}, cf. the description of set_attr() above.

This method should be considered experimental.

ERRORS

If the conversion can't be initialized an exception is raised (using croak()).

Handling of conversion errors

Text::Iconv provides a class attribute raise_error and a corresponding class method for setting and getting its value. The handling of errors during conversion depends on the setting of this attribute. If raise_error is set to a true value, an exception is raised; otherwise, the convert() method only returns undef. By default raise_error is false. Example usage:

  Text::Iconv->raise_error(1);     # Conversion errors raise exceptions
  Text::Iconv->raise_error(0);     # Conversion errors return undef
  $a = Text::Iconv->raise_error(); # Get current setting

Per-object handling of conversion errors

As an experimental feature, Text::Iconv also provides an instance attribute raise_error and a corresponding method for setting and getting its value. If raise_error is undef, the class-wide settings apply. If raise_error is 1 or 0 (true or false), the object settings override the class-wide settings.

Consult iconv(3) for details on errors that might occur.

Conversion of undef

Converting undef, e.g.,

  $converted = $converter->convert(undef);

always returns undef. This is not considered an error.

NOTES

The supported codesets, their names, the supported conversions, and the quality of the conversions are all system-dependent.

AUTHOR

Michael Piotrowski <mxp@dynalabs.de>