iconv (3)

NAME

       iconv - perform character set conversion

SYNOPSIS

       #include <iconv.h>

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

DESCRIPTION

       The argument cd must be a conversion descriptor created using the func-
       tion 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 *out-
       bytesleft 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  con-
       version 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 *out-
       bytesleft 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.
       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.

CONFORMING TO

       UNIX98

SEE ALSO

       iconv_open(3), iconv_close(3)

GNU                               2001-11-15                          iconv(3)