Ubuntu Manpage: iconv - codeset conversion

NAME

       iconv - codeset conversion

SYNOPSIS

       iconv [-cs] -f frommap -t tomap [file ...]

       iconv -f fromcode [-cs] [-t tocode [file ...]

       iconv -t tocode [-cs] [-f fromcode] [file ...]

       iconv -l

DESCRIPTION

       The  iconv  utility  shall  convert the encoding of characters in file from one codeset to
       another and write the results to standard output.

       When the options indicate that charmap  files  are  used  to  specify  the  codesets  (see
       OPTIONS), the codeset conversion shall be accomplished by performing a logical join on the
       symbolic character names in the two charmaps. The implementation need not support the  use
       of  charmap  files for codeset conversion unless the POSIX2_LOCALEDEF symbol is defined on
       the system.

OPTIONS

The iconv utility shall conform to the Base Definitions volume of IEEE Std 1003.1-2001,
Section 12.2, Utility Syntax Guidelines.

The following options shall be supported:

-c Omit any characters that are invalid in the codeset of the input file from the
output. When -c is not used, the results of encountering invalid characters in the
input stream (either those that are not characters in the codeset of the input file
or that have no corresponding character in the codeset of the output file) shall be
specified in the system documentation. The presence or absence of -c shall not
affect the exit status of iconv.

-f fromcodeset

Identify the codeset of the input file. The implementation shall recognize the
following two forms of the fromcodeset option-argument:

fromcode
The fromcode option-argument must not contain a slash character. It shall be
interpreted as the name of one of the codeset descriptions provided by the
implementation in an unspecified format. Valid values of fromcode are
implementation-defined.

frommap
The frommap option-argument must contain a slash character. It shall be
interpreted as the pathname of a charmap file as defined in the Base Definitions
volume of IEEE Std 1003.1-2001, Section 6.4, Character Set Description File. If the
pathname does not represent a valid, readable charmap file, the results are
undefined.

If this option is omitted, the codeset of the current locale shall be used.

-l Write all supported fromcode and tocode values to standard output in an unspecified
format.

-s Suppress any messages written to standard error concerning invalid characters. When
-s is not used, the results of encountering invalid characters in the input stream
(either those that are not valid characters in the codeset of the input file or
that have no corresponding character in the codeset of the output file) shall be
specified in the system documentation. The presence or absence of -s shall not
affect the exit status of iconv.

-t tocodeset
Identify the codeset to be used for the output file. The implementation shall
recognize the following two forms of the tocodeset option-argument:

tocode
The semantics shall be equivalent to the -f fromcode option.

tomap
The semantics shall be equivalent to the tomap option.

If this option is omitted, the codeset of the current locale shall be used.

If either -f or -t represents a charmap file, but the other does not (or is omitted), or
both -f and -t are omitted, the results are undefined.

OPERANDS

       The following operand shall be supported:

       file   A pathname of an input file. If no file  operands  are  specified,  or  if  a  file
              operand is '-' , the standard input shall be used.

STDIN

       The  standard  input  shall  be  used only if no file operands are specified, or if a file
       operand is '-' .

INPUT FILES

       The input file shall be a text file.

ENVIRONMENT VARIABLES

       The following environment variables shall affect the execution of iconv:

       LANG   Provide a default value for the internationalization variables that  are  unset  or
              null.  (See  the  Base  Definitions  volume  of  IEEE Std 1003.1-2001, Section 8.2,
              Internationalization Variables for the precedence of internationalization variables
              used to determine the values of locale categories.)

       LC_ALL If  set  to  a  non-empty  string  value,  override  the  values  of  all the other
              internationalization variables.

       LC_CTYPE
              Determine the locale for the interpretation of sequences of bytes of text  data  as
              characters  (for  example,  single-byte  as  opposed  to  multi-byte  characters in
              arguments). During translation of the file, this variable is superseded by the  use
              of the fromcode option-argument.

       LC_MESSAGES
              Determine  the  locale  that  should  be  used to affect the format and contents of
              diagnostic messages written to standard error.

       NLSPATH
              Determine the location of message catalogs for the processing of LC_MESSAGES .

ASYNCHRONOUS EVENTS

       Default.

STDOUT

       When the -l option is used, the standard output shall contain all supported  fromcode  and
       tocode values, written in an unspecified format.

       When  the  -l  option  is  not  used,  the  standard  output shall contain the sequence of
       characters read from the input files, translated to the specified  codeset.  Nothing  else
       shall be written to the standard output.

STDERR

       The standard error shall be used only for diagnostic messages.

OUTPUT FILES

       None.

EXTENDED DESCRIPTION

       None.

EXIT STATUS

       The following exit values shall be returned:

        0     Successful completion.

       >0     An error occurred.

CONSEQUENCES OF ERRORS

       Default.

       The following sections are informative.

APPLICATION USAGE

       The  user  must  ensure that both charmap files use the same symbolic names for characters
       the two codesets have in common.

EXAMPLES

       The following example converts the contents of file mail.x400 from  the  ISO/IEC 6937:1994
       standard  codeset  to  the ISO/IEC 8859-1:1998 standard codeset, and stores the results in
       file mail.local:

              iconv -f IS6937 -t IS8859 mail.x400 > mail.local

RATIONALE

       The iconv utility can be used portably only when the user provides two  charmap  files  as
       option-arguments. This is because a single charmap provided by the user cannot reliably be
       joined with the names in a system-provided character set description. The valid values for
       fromcode and tocode are implementation-defined and do not have to have any relation to the
       charmap mechanisms. As an aid to interactive users, the -l option  was  adopted  from  the
       Plan  9  operating  system.  It writes information concerning these implementation-defined
       values. The format is unspecified because there are  many  possible  useful  formats  that
       could  be  chosen,  such  as a matrix of valid combinations of fromcode and tocode. The -l
       option is not intended for shell script usage; conforming applications will  have  to  use
       charmaps.

FUTURE DIRECTIONS

       None.

COPYRIGHT

       Portions  of  this  text  are  reprinted  and  reproduced in electronic form from IEEE Std
       1003.1, 2003 Edition, Standard for Information Technology  --  Portable  Operating  System
       Interface  (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by
       the Institute of Electrical and Electronics Engineers, Inc and  The  Open  Group.  In  the
       event  of  any  discrepancy  between this version and the original IEEE and The Open Group
       Standard, the original IEEE and The Open Group  Standard  is  the  referee  document.  The
       original Standard can be obtained online at http://www.opengroup.org/unix/online.html .