Originální popis anglicky:
iconv - codeset conversion
Návod, kniha: POSIX Programmer's Manual
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
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.
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
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 .
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 6937:1994 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
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.
None.
gencat
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
.
