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 malicious 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)
.Rs "The FreeBSD Security Architecture"
.Re (See "/usr/share/doc/{to be decided}".)
STANDARDS
HISTORY
