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STRNCPY(3P)                POSIX Programmer's Manual               STRNCPY(3P)
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.
NAME
       stpncpy, strncpy -- copy fixed length string, returning  a  pointer  to
       the array end
SYNOPSIS
       #include <string.h>
       char *stpncpy(char *restrict s1, const char *restrict s2, size_t n);
       char *strncpy(char *restrict s1, const char *restrict s2, size_t n);
DESCRIPTION
       For  strncpy():  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.1-2008 defers to the ISO C standard.
       The stpncpy() and strncpy() functions shall copy not more than n  bytes
       (bytes  that  follow  a  NUL  character  are not copied) from the array
       pointed to by s2 to the array pointed to by s1.
       If the array pointed to by s2 is a string that is shorter than n bytes,
       NUL characters shall be appended to the copy in the array pointed to by
       s1, until n bytes in all are written.
       If copying takes place between objects that overlap,  the  behavior  is
       undefined.
RETURN VALUE
       If  a  NUL character is written to the destination, the stpncpy() func-
       tion shall return the address of the first such NUL character.   Other-
       wise, it shall return &s1[n].
       The strncpy() function shall return s1.
       No return values are reserved to indicate an error.
ERRORS
       No errors are defined.
       The following sections are informative.
EXAMPLES
       None.
APPLICATION USAGE
       Applications  must provide the space in s1 for the n bytes to be trans-
       ferred, as well as ensure that the s2 and s1 arrays do not overlap.
       Character movement is performed differently  in  different  implementa-
       tions. Thus, overlapping moves may yield surprises.
       If  there  is  no  NUL character byte in the first n bytes of the array
       pointed to by s2, the result is not null-terminated.
RATIONALE
       None.
FUTURE DIRECTIONS
       None.
SEE ALSO
       strcpy(), wcsncpy()
       The Base Definitions volume of POSIX.1-2008, <string.h>
COPYRIGHT
       Portions of this text are reprinted and reproduced in  electronic  form
       from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
       -- Portable Operating System Interface (POSIX),  The  Open  Group  Base
       Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri-
       cal and Electronics Engineers,  Inc  and  The  Open  Group.   (This  is
       POSIX.1-2008  with  the  2013  Technical Corrigendum 1 applied.) 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.unix.org/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.ker-
       nel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group                  2013                          STRNCPY(3P)