void *bsearch( void *key, void *base, int nelem, int width,
			int (*fcmp )())

	- prototype in stdlib.h

	- does binary search for items in a table which is
	  ALREADY sorted in ascending order
	- base points to 0th element of table
	- nelem contains number of entries in table
	- width contains number of bytes in each entry
	- key points to the search key

	- fcmp() points to comparison routine, where key and elem are
	  passed to it as pointers.  Function fcmp() returns:

		integer < 0 if search key < elem;
		integer = 0 if equal;
		returns > 0 if search key > elem

	- returns 0 if no match found, else address of first
	  entry that matches