Libc-763.12.tar.gz

[apple/libc.git] / string / strcpy.3

diff --git a/string/strcpy.3 b/string/strcpy.3
index 9742ef4f7759d7110968c661a0735c41b33e1185..e1fbdc1bbac76e29a82d43a2e0ad0d5afa480f9c 100644 (file)
--- a/string/strcpy.3
+++ b/string/strcpy.3
@@ -13,10 +13,6 @@
 .\" 2. Redistributions in binary form must reproduce the above copyright
 .\"    notice, this list of conditions and the following disclaimer in the
 .\"    documentation and/or other materials provided with the distribution.
-.\" 3. All advertising materials mentioning features or use of this software
-.\"    must display the following acknowledgement:
-.\"    This product includes software developed by the University of
-.\"    California, Berkeley and its contributors.
 .\" 4. Neither the name of the University nor the names of its contributors
 .\"    may be used to endorse or promote products derived from this software
 .\"    without specific prior written permission.
@@ -34,15 +30,13 @@
 .\" SUCH DAMAGE.
 .\"
 .\"     @(#)strcpy.3   8.1 (Berkeley) 6/4/93
-.\" $FreeBSD: src/lib/libc/string/strcpy.3,v 1.24 2002/12/19 09:40:24 ru Exp $
+.\" $FreeBSD: src/lib/libc/string/strcpy.3,v 1.28 2009/04/07 13:42:53 trasz Exp $
 .\"
-.Dd August 9, 2001
+.Dd February 28, 2009
 .Dt STRCPY 3
 .Os
 .Sh NAME
-.Nm stpcpy ,
-.Nm strcpy ,
-.Nm strncpy
+.Nm stpcpy, stpncpy, strcpy , strncpy
 .Nd copy strings
 .Sh LIBRARY
 .Lb libc
@@ -54,6 +48,12 @@
 .Fa "const char *s2"
 .Fc
 .Ft char *
+.Fo stpncpy
+.Fa "char *restrict s1"
+.Fa "const char *restrict s2"
+.Fa "size_t n"
+.Fc
+.Ft char *
 .Fo strcpy
 .Fa "char *restrict s1"
 .Fa "const char *restrict s2"
@@ -79,8 +79,10 @@ to
 character).
 .Pp
 The
+.Fn stpncpy
+and
 .Fn strncpy
-function copies at most
+functions copy at most
 .Fa n
 characters from
 .Fa s2
@@ -114,10 +116,21 @@ return
 .Fa s1 .
 The
 .Fn stpcpy
-function returns a pointer to the terminating
+and
+.Fn stpncpy
+functions return a pointer to the terminating
 .Ql \e0
 character of
 .Fa s1 .
+If
+.Fn stpncpy
+does not terminate
+.Fa s1
+with a
+.Dv NUL
+character, it instead returns a pointer to
+.Li s1[n]
+(which does not necessarily refer to a valid memory location.)
 .Sh EXAMPLES
 The following sets
 .Va chararray
@@ -173,27 +186,33 @@ This could be better achieved using
 as shown in the following example:
 .Pp
 .Dl "(void)strlcpy(buf, input, sizeof(buf));"
-.Pp
-Note that, because
-.Xr strlcpy 3
-is not defined in any standards, it should
-only be used when portability is not a concern.
 .Sh SECURITY CONSIDERATIONS
 The
-.Fn strcpy
-function is easily misused in a manner which enables malicious users
+.Fn strcpy ,
+.Fn strncpy ,
+.Fn stpcpy ,
+and
+.Fn stpncpy
+functions are easily misused in a manner which enables malicious users
 to arbitrarily change a running program's functionality through a
 buffer overflow attack.
 (See
 the FSA
 and
 .Sx EXAMPLES . )
+.Pp
+It is recommended that
+.Xr strlcpy 3
+be used instead as a way to avoid such problems.
+.Xr strlcpy 3
+is not defined in any standards, but it has been adopted by most major libc implementations.
 .Sh SEE ALSO
 .Xr bcopy 3 ,
 .Xr memccpy 3 ,
 .Xr memcpy 3 ,
 .Xr memmove 3 ,
-.Xr strlcpy 3
+.Xr strlcpy 3 ,
+.Xr wcscpy 3
 .Sh STANDARDS
 The
 .Fn strcpy
@@ -204,14 +223,16 @@ conform to
 .St -isoC .
 The
 .Fn stpcpy
-function is an MS-DOS and GNUism.
-The
-.Fn stpcpy
-function
-conforms to no standard.
+and
+.Fn stpncpy
+functions conform to
+.St -p1003.1-2008 .
 .Sh HISTORY
 The
 .Fn stpcpy
 function first appeared in
 .Fx 4.4 ,
-coming from 1998-vintage Linux.
+and
+.Fn stpncpy
+was added in
+.Fx 8.0 .