.\" DO NOT MODIFY THIS FILE!  It was generated by gdoc.
.TH "idn2_to_ascii_4i2" 3 "2.3.1.48-1925" "libidn2" "libidn2"
.SH NAME
idn2_to_ascii_4i2 \- API function
.SH SYNOPSIS
.B #include <idn2.h>
.sp
.BI "int idn2_to_ascii_4i2(const uint32_t * " input ", size_t " inlen ", char ** " output ", int " flags ");"
.SH ARGUMENTS
.IP "const uint32_t * input" 12
zero terminated input Unicode (UCS\-4) string.
.IP "size_t inlen" 12
number of elements in  \fIinput\fP .
.IP "char ** output" 12
pointer to newly allocated zero\-terminated output string.
.IP "int flags" 12
optional \fBidn2_flags\fP to modify behaviour.
.SH "DESCRIPTION"
The ToASCII operation takes a sequence of Unicode code points that make
up one domain label and transforms it into a sequence of code points in
the ASCII range (0..7F). If ToASCII succeeds, the original sequence and
the resulting sequence are equivalent labels.

It is important to note that the ToASCII operation can fail.
ToASCII fails if any step of it fails. If any step of the
ToASCII operation fails on any label in a domain name, that domain
name MUST NOT be used as an internationalized domain name.
The method for dealing with this failure is application\-specific.

The inputs to ToASCII are a sequence of code points.

ToASCII never alters a sequence of code points that are all in the ASCII
range to begin with (although it could fail). Applying the ToASCII operation multiple
effect as applying it just once.

The default behavior of this function (when flags are zero) is to apply
the IDNA2008 rules without the TR46 amendments. As the TR46
non\-transitional processing is nowadays ubiquitous, when unsure, it is
recommended to call this function with the \fBIDN2_NONTRANSITIONAL\fP
and the \fBIDN2_NFC_INPUT\fP flags for compatibility with other software.

Return value: Returns \fBIDN2_OK\fP on success, or error code.
.SH "SINCE"
2.1.1
.SH "SEE ALSO"
The full documentation for
.B libidn2
is maintained as a Texinfo manual.  If the
.B info
and
.B libidn2
programs are properly installed at your site, the command
.IP
.B info libidn2
.PP
should give you access to the complete manual.
As an alternative you may obtain the manual from:
.IP
.B https://www.gnu.org/software/libidn/libidn2/manual/
.PP