ICONV_OPEN(3P)

PROLOG
This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

NAME
iconv_open - codeset conversion allocation function

SYNOPSIS

#include <iconv.h>

iconv_t iconv_open(const char *tocode, const char *fromcode);

DESCRIPTION

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>.

RETURN VALUE

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.

ERRORS

The iconv_open() function may fail if:

EMFILE
    {OPEN_MAX} file descriptors are currently open in the calling process.

ENFILE
    Too many files are currently open in the system.

ENOMEM
    Insufficient storage space is available.

EINVAL
    The conversion specified by fromcode and tocode is not supported by the implementation.

The following sections are informative.

EXAMPLES

None.

APPLICATION USAGE

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.

RATIONALE

None.

FUTURE DIRECTIONS

None.

SEE ALSO

iconv(), iconv_close(), the Base Definitions volume of IEEE Std 1003.1-2001, <fcntl.h>, <iconv.h>

COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .