'\" et
.TH WCTRANS "3P" 2017 "IEEE/The Open Group" "POSIX Programmer's Manual"
.\"
.SH 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.
.\"
.SH NAME
wctrans,
wctrans_l
\(em define character mapping
.SH SYNOPSIS
.LP
.nf
#include <wctype.h>
.P
wctrans_t wctrans(const char *\fIcharclass\fP);
wctrans_t wctrans_l(const char *\fIcharclass\fP, locale_t \fIlocale\fP);
.fi
.SH DESCRIPTION
For
\fIwctrans\fR():
The functionality described on this reference page is aligned with the
ISO\ C standard. Any conflict between the requirements described here and the
ISO\ C standard is unintentional. This volume of POSIX.1\(hy2017 defers to the ISO\ C standard.
.P
The
\fIwctrans\fR()
and
\fIwctrans_l\fR()
functions are defined for valid character mapping names identified
in the current locale. The
.IR charclass
is a string identifying a generic character mapping name for which
codeset-specific information is required. The following character
mapping names are defined in all locales:
.BR tolower
and
.BR toupper .
.P
These functions shall return a value of type
.BR wctrans_t ,
which can be used as the second argument to subsequent calls of
\fItowctrans\fR()
and
\fItowctrans_l\fR().
.P
The
\fIwctrans\fR()
and
\fIwctrans_l\fR()
functions shall determine values of
.BR wctrans_t
according to the rules of the coded character set defined by character
mapping information in the current locale
or in the locale represented by
.IR locale ,
respectively (category
.IR LC_CTYPE ).
.P
The values returned by
\fIwctrans\fR()
shall be valid until a call to
\fIsetlocale\fR()
that modifies the category
.IR LC_CTYPE .
.P
The values returned by
\fIwctrans_l\fR()
shall be valid only in calls to
\fItowctrans_l\fR()
with a locale represented by
.IR locale
with the same
.IR LC_CTYPE
category value.
.P
The behavior is undefined if the
.IR locale
argument to
\fIwctrans_l\fR()
is the special locale object LC_GLOBAL_LOCALE or is not a valid locale
object handle.
.SH "RETURN VALUE"
The
\fIwctrans\fR()
and
\fIwctrans_l\fR()
functions shall return 0 and may set
.IR errno
to indicate the error if the given character mapping name is not valid
for the current locale (category
.IR LC_CTYPE );
otherwise, they shall return a non-zero object of type
.BR wctrans_t
that can be used in calls to
\fItowctrans\fR()
and
\fItowctrans_l\fR().
.SH ERRORS
These functions may fail if:
.TP
.BR EINVAL
The character mapping name pointed to by
.IR charclass
is not valid in the current locale.
.LP
.IR "The following sections are informative."
.SH EXAMPLES
None.
.SH "APPLICATION USAGE"
None.
.SH RATIONALE
None.
.SH "FUTURE DIRECTIONS"
None.
.SH "SEE ALSO"
.IR "\fItowctrans\fR\^(\|)"
.P
The Base Definitions volume of POSIX.1\(hy2017,
.IR "\fB<wctype.h>\fP"
.\"
.SH COPYRIGHT
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
http://www.opengroup.org/unix/online.html .
.PP
Any typographical or formatting errors that appear
in this page are most likely
to have been introduced during the conversion of the source files to
man page format. To report such errors, see
https://www.kernel.org/doc/man-pages/reporting_bugs.html .