Section: POSIX Programmer's Manual (3P)
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.
--- codeset conversion allocation function
iconv_t iconv_open(const char *tocode, const char *fromcode);
function shall return a conversion descriptor
that describes a conversion from the codeset specified by the string
pointed to by the
argument to the codeset specified by the string pointed to by the
argument. For state-dependent encodings, the conversion descriptor
shall be in a codeset-dependent initial shift state, ready for
immediate use with
and their permitted combinations are implementation-defined.
A conversion descriptor shall remain valid until it is closed by
or an implicit close.
If a file descriptor is used to implement conversion descriptors, the
FD_CLOEXEC flag shall be set; see
Upon successful completion,
shall return a conversion descriptor for use on subsequent calls to
shall return (iconv_t
)-1 and set
to indicate the error.
function may fail if:
All file descriptors available to the process are currently open.
Too many files are currently open in the system.
Insufficient storage space is available.
The conversion specified by
is not supported by the implementation.
The following sections are informative.
Some implementations of
to allocate space for internal buffer areas. The
function may fail if there is insufficient storage space to accommodate
Conforming applications must assume that conversion descriptors are not
valid after a call to one of the
Application developers should consult the system documentation to
determine the supported codesets and their naming schemes.
The Base Definitions volume of POSIX.1-2017,
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1-2017, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 7, 2018 Edition,
Copyright (C) 2018 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
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