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32 .\" @(#)strcpy.3 8.1 (Berkeley) 6/4/93
49 .Fn stpcpy "char * restrict dst" "const char * restrict src"
51 .Fn stpncpy "char * restrict dst" "const char * restrict src" "size_t len"
53 .Fn strcpy "char * restrict dst" "const char * restrict src"
55 .Fn strncpy "char * restrict dst" "const char * restrict src" "size_t len"
66 (including the terminating
74 functions copy at most
104 the result is undefined
122 functions return a pointer to the terminating
132 character, it instead returns a pointer to
134 (which does not necessarily refer to a valid memory location.)
139 .Dq Li abc\e0\e0\e0 :
140 .Bd -literal -offset indent
143 (void)strncpy(chararray, "abc", sizeof(chararray));
150 .Bd -literal -offset indent
153 (void)strncpy(chararray, "abcdefgh", sizeof(chararray));
161 because the length of the source string is greater than or equal
162 to the length argument.
164 The following copies as many characters from
170 terminates the result.
177 terminate the string itself, this must be done explicitly.
178 .Bd -literal -offset indent
181 (void)strncpy(buf, input, sizeof(buf) - 1);
182 buf[sizeof(buf) - 1] = '\e0';
185 This could be better achieved using
187 as shown in the following example:
189 .Dl "(void)strlcpy(buf, input, sizeof(buf));"
214 function first appeared in
220 .Sh SECURITY CONSIDERATIONS
221 All of the functions documented in this manual page are easily misused in a
222 manner which enables malicious users to arbitrarily change a running program's
223 functionality through a buffer overflow attack.
225 It is strongly suggested that the
227 function be used in almost all cases.
229 For some, but not all, fixed-length records, non-terminated strings may be both
231 In that specific case, the
233 function may be most sensible.