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STRCPY(3)	       FreeBSD Library Functions Manual		     STRCPY(3)

NAME
     strcpy, strncpy --	copy strings

LIBRARY
     Standard C	Library	(libc, -lc)

SYNOPSIS
     #include <string.h>

     char *
     stpcpy(char *dst, const char *src);

     char *
     strcpy(char * restrict dst, const char * restrict src);

     char *
     strncpy(char * restrict dst, const	char * restrict	src, size_t len);

DESCRIPTION
     The stpcpy() and strcpy() functions copy the string src to	dst (including
     the terminating `\0' character.)

     The strncpy() function copies at most len characters from src into	dst.
     If	src is less than len characters	long, the remainder of dst is filled
     with `\0' characters.  Otherwise, dst is not terminated.

RETURN VALUES
     The strcpy() and strncpy()	functions return dst.  The stpcpy() function
     returns a pointer to the terminating `\0' character of dst.

EXAMPLES
     The following sets	chararray to ``abc\0\0\0'':

	   char	chararray[6];

	   (void)strncpy(chararray, "abc", sizeof(chararray));

     The following sets	chararray to ``abcdef'':

	   char	chararray[6];

	   (void)strncpy(chararray, "abcdefgh",	sizeof(chararray));

     Note that it does not NUL terminate chararray because the length of the
     source string is greater than or equal to the length argument.

     The following copies as many characters from input	to buf as will fit and
     NUL terminates the	result.	 Because strncpy() does	not guarantee to NUL
     terminate the string itself, this must be done explicitly.

	   char	buf[1024];

	   (void)strncpy(buf, input, sizeof(buf) - 1);
	   buf[sizeof(buf) - 1]	= '\0';

     This could	be better achieved using strlcpy(3), as	shown in the following
     example:

	   (void)strlcpy(buf, input, sizeof(buf));

     Note that because strlcpy(3) is not defined in any	standards, it should
     only be used when portability is not a concern.

SECURITY CONSIDERATIONS
     The strcpy() function is easily misused in	a manner which enables mali-
     cious users to arbitrarily	change a running program's functionality
     through a buffer overflow attack.	(See the FSA and EXAMPLES.)

SEE ALSO
     bcopy(3), memccpy(3), memcpy(3), memmove(3), strlcpy(3)

     The FreeBSD Security Architecture.	 (See /usr/share/doc/{to be decided}.)

STANDARDS
     The strcpy() and strncpy()	functions conform to ISO/IEC 9899:1990
     (``ISO C90'').  The stpcpy() function is an MS-DOS	and GNUism.  The
     stpcpy() function conforms	to no standard.

HISTORY
     The stpcpy() function first appeared in FreeBSD 4.4, coming from
     1998-vintage Linux.

FreeBSD	6.0			August 9, 2001			   FreeBSD 6.0

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | EXAMPLES | SECURITY CONSIDERATIONS | SEE ALSO | STANDARDS | HISTORY

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