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 (con-
       sult the corresponding Linux manual page for details of Linux behavior), or the  interface  may  not  be  implemented  on
       Linux.

NAME
       strncpy - copy part of a string

SYNOPSIS
       #include <string.h>

       char *strncpy(char *restrict s1, const char *restrict s2, size_t n);


DESCRIPTION
       The  strncpy()  function  shall  copy not more than n bytes (bytes that follow a null byte are not copied) from the array
       pointed to by s2 to the array pointed to by s1.  If copying takes place between objects that  overlap,  the  behavior  is
       undefined.

       If  the  array pointed to by s2 is a string that is shorter than n bytes, null bytes shall be appended to the copy in the
       array pointed to by s1, until n bytes in all are written.

RETURN VALUE
       The strncpy() function shall return s1; no return value is reserved to indicate an error.

ERRORS
       No errors are defined.

       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       Character movement is performed differently in different implementations.  Thus, overlapping moves may yield surprises.

       If there is no null 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(), the Base Definitions volume of IEEE Std 1003.1-2001, <string.h>

COPYRIGHT
       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003  Edition,  Standard  for
       Information  Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copy-
       right (C) 2001-2003 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.open-
       group.org/unix/online.html .



IEEE/The Open Group                                           2003                                                   STRNCPY(3P)