strtok_s如何标记char *？

Question

It seems to have modified the original string that I wanted to split specifying tokens.

how does it return back a substring if it can't copy from memory?

I'm also looking for an alternative that accepts a const char* Or doesn't modify the orignal string.

Or is it safe to just const_cast the string to remove the const property and let it be handled by strtok_s(char*, const char*, char**) .?

Answer 1

strtok_s et al do modify the strings passed in, so no, you can't pass in a const_cast d constant string. What it does is if it finds a delimiter, it replaces that delimiter with a NUL terminator to separate the string into two pieces. It then returns a pointer to the first part, which is now the desired null-terminated token.

Answer 2

如果您不想修改原始字符串，可以strtok_s其复制，然后strtok_s其复制。