Memcpy with beginning and end values? c++?

I'm trying to parse a character array into tokens. I have beginning and ending positions for the token within the array, and i've used malloc to appropriate the correct number of bytes for a character array (stored in an array of char pointers). However, memcpy only have 3 parameters: destination, source, numBytes. Is there some way to use memcpy to specify a starting and ending position within the source array?