|
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)
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.
iconv — codeset conversion
iconv [−cs] −f frommap −t tomap [file...]
iconv −f fromcode [−cs] [−t tocode] [file...]
iconv −t tocode [−cs] [−f fromcode] [file...]
iconv −l
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.
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.
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.
The standard input shall be used only if no file operands are
specified, or if a file operand is '−'.
The input file shall be a text file.
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.
Default.
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.
The standard error shall be used only for diagnostic messages.
None.
None.
The following exit values shall be returned:
0 Successful completion.
>0 An error occurred.
Default.
The following sections are informative.
The user must ensure that both charmap files use the same symbolic
names for characters the two codesets have in common.
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
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.
None.
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
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)