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'\" t
.\" Copyright, the authors of the Linux man-pages project
.\"
.\" SPDX-License-Identifier: GPL-2.0-or-later
.\"
.TH wcpncpy 3 2025-07-11 "Linux man-pages (unreleased)"
.SH NAME
wcpncpy \- copy a fixed-size string of wide characters,
returning a pointer to its end
.SH LIBRARY
Standard C library
.RI ( libc ,\~ \-lc )
.SH SYNOPSIS
.nf
.B #include <wchar.h>
.P
.BR "wchar_t *wcpncpy(" "size_t n;"
.BI " wchar_t " dest "[restrict " n ],
.BI " const wchar_t *restrict " src ,
.BI " size_t " n );
.fi
.P
.RS -4
Feature Test Macro Requirements for glibc (see
.BR feature_test_macros (7)):
.RE
.P
.BR wcpncpy ():
.nf
Since glibc 2.10:
_POSIX_C_SOURCE >= 200809L
Before glibc 2.10:
_GNU_SOURCE
.fi
.SH DESCRIPTION
The
.BR wcpncpy ()
function is the wide-character equivalent
of the
.BR stpncpy (3)
function.
It copies at most
.I n
wide characters from the wide-character
string pointed to by
.IR src ,
including the terminating null wide (L\[aq]\[rs]0\[aq]),
to the array pointed to by
.IR dest .
Exactly
.I n
wide characters are
written at
.IR dest .
If the length
.I wcslen(src)
is smaller than
.IR n ,
the remaining wide characters in the array pointed to
by
.I dest
are filled with L\[aq]\[rs]0\[aq] characters.
If the length
.I wcslen(src)
is greater than or equal
to
.IR n ,
the string pointed to by
.I dest
will
not be L\[aq]\[rs]0\[aq] terminated.
.P
The strings may not overlap.
.P
The programmer must ensure that there is room for at least
.I n
wide
characters at
.IR dest .
.SH RETURN VALUE
.BR wcpncpy ()
returns a pointer to
one past the last non-null wide character written,
that is,
.IR dest\~+\~wcsnlen(src,\~n) .
.SH ATTRIBUTES
For an explanation of the terms used in this section, see
.BR attributes (7).
.TS
allbox;
lbx lb lb
l l l.
Interface Attribute Value
T{
.na
.nh
.BR wcpncpy ()
T} Thread safety MT-Safe
.TE
.SH STANDARDS
POSIX.1-2008.
.SH SEE ALSO
.BR stpncpy (3),
.BR wcsncpy (3)
|
