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32 .\" @(#)strcpy.3 8.1 (Berkeley) 6/4/93
33 .\" $FreeBSD: src/lib/libc/string/strcpy.3,v 1.26 2007/01/09 00:28:12 imp Exp $
34 .\" $DragonFly: src/lib/libc/string/strcpy.3,v 1.3 2005/08/05 22:35:10 swildner Exp $
48 .Fn stpcpy "char *dst" "const char *src"
50 .Fn stpncpy "char * restrict dst" "const char * restrict src" "size_t len"
52 .Fn strcpy "char * restrict dst" "const char * restrict src"
54 .Fn strncpy "char * restrict dst" "const char * restrict src" "size_t len"
65 (including the terminating
73 functions copy at most
106 functions return a pointer to the terminating
112 does not null-terminate
114 because the length of
118 then it returns a pointer to
120 which may not be valid.
125 .Dq Li abc\e0\e0\e0 :
126 .Bd -literal -offset indent
129 (void)strncpy(chararray, "abc", sizeof(chararray));
136 .Bd -literal -offset indent
139 (void)strncpy(chararray, "abcdefgh", sizeof(chararray));
147 because the length of the source string is greater than or equal
148 to the length argument.
150 The following copies as many characters from
156 terminates the result.
163 terminate the string itself, this must be done explicitly.
164 .Bd -literal -offset indent
167 (void)strncpy(buf, input, sizeof(buf) - 1);
168 buf[sizeof(buf) - 1] = '\e0';
171 This could be better achieved using
173 as shown in the following example:
175 .Dl "(void)strlcpy(buf, input, sizeof(buf));"
179 is not defined in any standards, it should
180 only be used when portability is not a concern.
181 .Sh SECURITY CONSIDERATIONS
184 function is easily misused in a manner which enables malicious users
185 to arbitrarily change a running program's functionality through a
186 buffer overflow attack.
214 function first appeared in
216 coming from 1998-vintage Linux