Originální popis anglicky:
iconv - perform character set conversion
Návod, kniha: Linux Programmer's Manual
#include <iconv.h>
size_t iconv(iconv_t cd,
char **inbuf, size_t *inbytesleft,
char **outbuf, size_t *outbytesleft);
The argument
cd must be a conversion descriptor created using the
function
iconv_open.
The main case is when
inbuf is not NULL and
*inbuf is not NULL. In
this case, the
iconv function converts the multibyte sequence starting
at
*inbuf to a multibyte sequence starting at
*outbuf. At most
*inbytesleft bytes, starting at
*inbuf, will be read. At most
*outbytesleft bytes, starting at
*outbuf, will be written.
The
iconv function converts one multibyte character at a time, and for
each character conversion it increments
*inbuf and decrements
*inbytesleft by the number of converted input bytes, it increments
*outbuf and decrements
*outbytesleft by the number of converted
output bytes, and it updates the conversion state contained in
cd. The
conversion can stop for four reasons:
1. An invalid multibyte sequence is encountered in the input. In this case it
sets
errno to
EILSEQ and returns (size_t)(-1).
*inbuf is
left pointing to the beginning of the invalid multibyte sequence.
2. The input byte sequence has been entirely converted, i.e.
*inbytesleft
has gone down to 0. In this case
iconv returns the number of
non-reversible conversions performed during this call.
3. An incomplete multibyte sequence is encountered in the input, and the input
byte sequence terminates after it. In this case it sets
errno to
EINVAL and returns (size_t)(-1).
*inbuf is left pointing to the
beginning of the incomplete multibyte sequence.
4. The output buffer has no more room for the next converted character. In this
case it sets
errno to
E2BIG and returns (size_t)(-1).
A different case is when
inbuf is NULL or
*inbuf is NULL, but
outbuf is not NULL and
*outbuf is not NULL. In this case, the
iconv function attempts to set
cd's conversion state to the
initial state and store a corresponding shift sequence at
*outbuf. At
most
*outbytesleft bytes, starting at
*outbuf, will be written.
If the output buffer has no more room for this reset sequence, it sets
errno to
E2BIG and returns (size_t)(-1). Otherwise it increments
*outbuf and decrements
*outbytesleft by the number of bytes
written.
A third case is when
inbuf is NULL or
*inbuf is NULL, and
outbuf is NULL or
*outbuf is NULL. In this case, the
iconv function sets
cd's conversion state to the initial state.
The
iconv function returns the number of characters converted in a
non-reversible way during this call; reversible conversions are not counted.
In case of error, it sets
errno and returns (size_t)(-1).
The following errors can occur, among others:
- E2BIG
- There is not sufficient room at *outbuf.
- EILSEQ
- An invalid multibyte sequence has been encountered in the
input.
- EINVAL
- An incomplete multibyte sequence has been encountered in
the input.
UNIX98
iconv_close(3),
iconv_open(3)
