Content-type: text/html Man page of iconv

iconv

Section: C Library Functions (3)
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NAME

iconv - Converts a string of characters from one codeset to another codeset  

LIBRARY

The iconv Library (libiconv.so, libiconv.a)  

SYNOPSIS

#include <iconv.h>

size_t iconv(
        iconv_t cd,
        const char **inbuf,
        size_t *inbytesleft,
        char **outbuf,
        size_t *outbytesleft);

The following nonstandard interface is supported in libiconv only for backward compatibility with versions of Tru64 UNIX earlier than Version 4.0:

size_t iconv(
        iconv_t cd,
        char **inbuf,
        size_t *inbytesleft,
        char **outbuf,
        size_t *outbytesleft);  

STANDARDS

Interfaces documented on this reference page conform to industry standards as follows:

iconv(): XPG4

Refer to the standards(5) reference page for more information about industry standards and associated tags.  

PARAMETERS

Specifies the conversion descriptor that points to the correct codeset converter Points to a variable that points to the beginning of a buffer that contains the characters to be converted Points to an integer that contains the number of bytes in inbuf still to be converted Points to a variable that points to the buffer that contains the characters that have been converted Points to an integer that contains the number of free bytes in outbuf  

DESCRIPTION

The iconv() function converts a string of characters in inbuf into a different codeset and returns the results in outbuf. The required converter is identified by cd, which must be a valid descriptor returned by a previous successful call to the iconv_open() function.

On calling, the inbytesleft parameter indicates the number of bytes in inbuf to be converted and outbytesleft indicates the number of available bytes in outbuf.

For codesets that include shift-state sequences, a call to iconv() in which inbuf is or points to a null pointer places the cd conversion descriptor into its initial shift state. In this case, as long as outbuf is not (or does not point to) a null pointer, the call places in outbuf the byte sequence that changes the output buffer to its initial shift state. If the output buffer is not large enough to hold the entire reset sequence, the call fails and sets errno to [E2BIG]. Any subsequent calls in which inbuf is not (or does not point to) a null pointer cause the conversion to take place from the current state of the conversion descriptor. See the RESTRICTIONS section for information about support of shift-state encoding on Tru64 UNIX systems.

If a sequence of input bytes does not form a character that is valid in the input codeset, conversion stops after the previous successfully converted character. If the input buffer ends with an incomplete character or shift sequence, conversion stops after the last byte sequence that was successfully converted to a character. If the output is not large enough to hold the entire sequence of converted characters, conversion stops just prior to the input byte sequence that would cause the output buffer to overflow.

On return from the call: The inbuf value is updated to point to the byte following the last byte used successfully in conversion The inbytesleft value is decremented to reflect the number of input bytes still not converted The outbuf value is updated to point to the byte following the last output byte of successfully converted data The outbytesleft value is decremented to reflect the number of bytes still available in the output buffer. For codesets that include shift-state encoding, the conversion descriptor is updated to reflect the shift state in effect at the end of the last successfully converted byte sequence.

It is possible for input data to include a character that is valid in the input codeset but for which an identical character does not exist in the output codeset. The output character for such cases is defined by the converter that iconv() applies when converting from one particular codeset to another. In other words, the output character in this case can vary from one codeset converter to another.  

RESTRICTIONS

Currently, the Tru64 UNIX product does not include locales whose codesets use shift-state encoding. Some sections of this reference page refer to iconv() behavior with respect to conversion of shift sequences. This information is included only for your convenience in developing portable applications that run on multiple platforms, some of which may supply locales whose codesets do use shift-state encoding.  

RETURN VALUES

The iconv() function updates the variables pointed to by the call arguments to reflect the extent of the conversion and returns the number of non-identical conversions performed. If the function is successful and converts the entire input string, the value pointed to by inbytesleft will be 0 (zero).

If an error occurs, the function returns (size_t)-1 and sets errno to indicate the condition.  

ERRORS

If any of the following conditions occur, the iconv() function sets errno to the corresponding value: The outbuf buffer is too small to contain all the converted characters. The character that causes the overflow is not converted and inbytesleft indicates the bytes left to be converted, including the character that caused the overflow. The inbuf parameter points to the first byte of the characters left to convert. The cd parameter does not specify a valid converter descriptor. An input character does not belong to the input codeset. No conversion is attempted on the invalid character and inbytesleft indicates the bytes left to be converted, including the first byte of the invalid character. The inbuf parameter points to the first byte of the invalid character sequence.

The values of outbuf and outbytesleft are updated according to the number of characters that were previously converted. The last character or shift sequence in the inbuf parameter was not complete. The inbytesleft parameter indicates the number of input bytes still not converted.
 

RELATED INFORMATION

Functions: iconv_close(3), iconv_open(3)

Commands: iconv(1), genxlt(1)

Others: iconv_intro(5), standards(5) delim off


 

Index

NAME
LIBRARY
SYNOPSIS
STANDARDS
PARAMETERS
DESCRIPTION
RESTRICTIONS
RETURN VALUES
ERRORS
RELATED INFORMATION

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Time: 02:42:03 GMT, October 02, 2010