ICONV(3)		   Linux Programmer's Manual		      ICONV(3)



NAME
       iconv - perform character set conversion

SYNOPSIS
       #include 

       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(3).

       The main case is when inbuf is not NULL and *inbuf  is  not  NULL.   In
       this  case, the iconv() function converts the multibyte sequence start-
       ing 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.   If  the
       character  encoding  of the input is stateful, the iconv() function can
       also convert a sequence of input bytes to an update to  the  conversion
       state  without producing any output bytes; such input is called a shift
       sequence.  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,  that  is,
       *inbytesleft has gone down to 0.	 In this case iconv() returns the num-
       ber 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.

RETURN VALUE
       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.

ERRORS
       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.

VERSIONS
       This function is available in glibc since version 2.1.

CONFORMING TO
       POSIX.1-2001.

SEE ALSO
       iconv_close(3), iconv_open(3)

COLOPHON
       This  page  is  part of release 3.22 of the Linux man-pages project.  A
       description of the project, and information about reporting  bugs,  can
       be found at http://www.kernel.org/doc/man-pages/.



GNU				  2008-09-08			      ICONV(3)