iconv_open(3p)
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 .