iconv_t iconv_open(const char *tocode, const char *fromcode);
The iconv_open() function shall return a conversion descriptor that describes a conversion from the codeset specified by the string pointed to by the fromcode argument to the codeset specified by the string pointed to by the tocode argument. For state-dependent encodings, the conversion descriptor shall be in a codeset-dependent initial shift state, ready for immediate use with iconv().
Settings of fromcode and tocode and their permitted combinations are implementation-defined.
A conversion descriptor shall remain valid until it is closed by iconv_close() or an implicit close.
If a file descriptor is used to implement conversion descriptors, the FD_CLOEXEC flag shall be set; see <fcntl.h>.
Upon successful completion, iconv_open() shall return a conversion descriptor for use on subsequent calls to iconv(). Otherwise, iconv_open() shall return (iconv_t)-1 and set errno to indicate the error.
The iconv_open() function may fail if:
The following sections are informative.
Some implementations of iconv_open() use malloc() to allocate space for internal buffer areas. The iconv_open() function may fail if there is insufficient storage space to accommodate these buffers.
Conforming applications must assume that conversion descriptors are not valid after a call to one of the exec functions.
Application developers should consult the system documentation to determine the supported codesets and their naming schemes.
iconv() , iconv_close() , the Base Definitions volume of IEEE Std 1003.1-2001, <fcntl.h>, <iconv.h>