PROLOG | NAME | SYNOPSIS | DESCRIPTION | OPTIONS | OPERANDS | STDIN | INPUT FILES | ENVIRONMENT VARIABLES | ASYNCHRONOUS EVENTS | STDOUT | STDERR | OUTPUT FILES | EXTENDED DESCRIPTION | EXIT STATUS | CONSEQUENCES OF ERRORS | APPLICATION USAGE | EXAMPLES | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT

ICONV(1P)                 POSIX Programmer's Manual                ICONV(1P)

PROLOG         top

       This manual page is part of the POSIX Programmer's Manual.  The Linux
       implementation of this interface may differ (consult the
       corresponding Linux manual page for details of Linux behavior), or
       the interface may not be implemented on Linux.

NAME         top

       iconv — codeset conversion

SYNOPSIS         top

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

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

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

       iconv −l

DESCRIPTION         top

       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         top

       The iconv utility shall conform to the Base Definitions volume of
       POSIX.1‐2008, 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 POSIX.1‐2008, 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 −f
                           frommap 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         top

       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         top

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

INPUT FILES         top

       The input file shall be a text file.

ENVIRONMENT VARIABLES         top

       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 POSIX.1‐2008, 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         top

       Default.

STDOUT         top

       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         top

       The standard error shall be used only for diagnostic messages.

OUTPUT FILES         top

       None.

EXTENDED DESCRIPTION         top

       None.

EXIT STATUS         top

       The following exit values shall be returned:

        0    Successful completion.

       >0    An error occurred.

CONSEQUENCES OF ERRORS         top

       Default.

       The following sections are informative.

APPLICATION USAGE         top

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

EXAMPLES         top

       The following example converts the contents of file mail.x400 from
       the ISO/IEC 6937:2001 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         top

       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.

       The iconv utility may support the conversion between ASCII and
       EBCDIC-based encodings, but is not required to do so. In an XSI-
       compliant implementation, the dd utility is the only method
       guaranteed to support conversion between these two character sets.

FUTURE DIRECTIONS         top

       None.

SEE ALSO         top

       dd(1p), gencat(1p)

       The Base Definitions volume of POSIX.1‐2008, Section 6.4, Character
       Set Description File, Chapter 8, Environment Variables, Section 12.2,
       Utility Syntax Guidelines

COPYRIGHT         top

       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2013 Edition, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The Open
       Group Base Specifications Issue 7, Copyright (C) 2013 by the
       Institute of Electrical and Electronics Engineers, Inc and The Open
       Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1
       applied.) 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.unix.org/online.html .

       Any typographical or formatting errors that appear in this page are
       most likely to have been introduced during the conversion of the
       source files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                 2013                           ICONV(1P)

Pages that refer to this page: gencat(1p)