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.
#include <wchar.h> wchar_t *wcpncpy(wchar_t restrict *ws1, const wchar_t *restrict ws2, size_t n); wchar_t *wcsncpy(wchar_t *restrict ws1, const wchar_t *restrict ws2, size_t n);
For wcsncpy(): 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.1-2017 defers to the ISO C standard.
The wcpncpy() and wcsncpy() functions shall copy not more than n wide-character codes (wide-character codes that follow a null wide-character code are not copied) from the array pointed to by ws2 to the array pointed to by ws1. If copying takes place between objects that overlap, the behavior is undefined.
If the array pointed to by ws2 is a wide-character string that is shorter than n wide-character codes, null wide-character codes shall be appended to the copy in the array pointed to by ws1, until n wide-character codes in all are written.
If any null wide-character codes were written into the destination, the wcpncpy() function shall return the address of the first such null wide-character code. Otherwise, it shall return &ws1[n].
The wcsncpy() function shall return ws1.
No return values are reserved to indicate an error.
No errors are defined.
The following sections are informative.
If there is no null wide-character code in the first n wide-character codes of the array pointed to by ws2, the result is not null-terminated.
The Base Definitions volume of POSIX.1-2017, <wchar.h>
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 .
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 .
strncpy(3p), wchar.h(0p), wcscpy(3p).