👤
Home Man
Search
Today's Posts
Register

Linux & Unix Commands - Search Man Pages
Man Page or Keyword Search:
Select Section of Man Page:
Select Man Page Repository:

NetBSD 6.1.5 - man page for stpncpy (netbsd section 3)

STRCPY(3)			   BSD Library Functions Manual 			STRCPY(3)

NAME
     stpcpy, stpncpy, strcpy, strncpy -- copy strings

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <string.h>

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

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

     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 stpncpy() and strncpy() functions copy 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.  Oth-
     erwise, dst is not terminated.

RETURN VALUES
     The strcpy() and strncpy() functions return dst.  The stpcpy() and stpncpy() functions
     return a pointer to the terminating '\0' character of dst.  If stpncpy() does not terminate
     dst with a NUL character, it instead returns a pointer to dst[len] (which does not necessar-
     ily refer to a valid memory location.)

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 parameter.  strncpy() only NUL-terminates the destina-
     tion string when the length of the source string is less than the length parameter.

     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 and more simply 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.

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

STANDARDS
     The strcpy() and strncpy() functions conform to ISO/IEC 9899:1999 (``ISO C99'').  The
     stpcpy() and stpncpy() functions conform to IEEE Std 1003.1-2008 (``POSIX.1'').

HISTORY
     The stpcpy() and stpncpy() functions first appeared in NetBSD 6.0.

SECURITY CONSIDERATIONS
     The strcpy() and stpcpy() functions are easily misused in a manner which enables malicious
     users to arbitrarily change a running program's functionality through a buffer overflow
     attack.

BSD					   May 1, 2009					      BSD


All times are GMT -4. The time now is 03:34 PM.

Unix & Linux Forums Content Copyrightę1993-2018. All Rights Reserved.
×
UNIX.COM Login
Username:
Password:  
Show Password