.\" Copyright (c) Bruno Haible <haible@clisp.cons.org>
.\"
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.TH ICONV_OPEN 3  "November 27, 1999" "GNU" "Linux Programmer's Manual"
.SH NAME
iconv_open \- allocate descriptor for character set conversion
.SH SYNOPSIS
.nf
.B #include <iconv.h>
.sp
.BI "iconv_t iconv_open (const char* " tocode ", const char* " fromcode );
.fi
.SH DESCRIPTION
The \fBiconv_open\fP function allocates a conversion descriptor suitable
for converting byte sequences from character encoding \fIfromcode\fP to
character encoding \fItocode\fP.
.PP
The values permitted for \fIfromcode\fP and \fItocode\fP and the supported
combinations are system dependent. For the GNU C library, the permitted
values are listed by the \fBiconv --list\fP command, and all combinations
of the listed values are supported.
.PP
The resulting conversion descriptor can be used with \fBiconv\fP any number
of times. It remains valid until deallocated using \fBiconv_close\fP.
.PP
A conversion descriptor contains a conversion state. After creation using
\fBiconv_open\fP, the state is in the initial state. Using \fBiconv\fP
modifies the descriptor's conversion state. (This implies that a conversion
descriptor can not be used in multiple threads simultaneously.) To bring the
state back to the initial state, use \fBiconv\fP with NULL as \fIinbuf\fP
argument.
.SH "RETURN VALUE"
The \fBiconv_open\fP function returns a freshly allocated conversion
descriptor. In case of error, it sets \fBerrno\fP and returns (iconv_t)(-1).
.SH ERRORS
The following error can occur, among others:
.TP
.B EINVAL
The conversion from \fIfromcode\fP to \fItocode\fP is not supported by the
implementation.
.SH "CONFORMING TO"
UNIX98
.SH "SEE ALSO"
.BR iconv "(3), " iconv_close "(3), " iconv (1)