-/* Like xmemcoll, but S1 and S2 are known to be NUL delimited, thus
- no modifications to S1 and S2 are needed. */
+/* Compare S1 (with size S1SIZE) and S2 (with length S2SIZE) according
+ to the LC_COLLATE locale. S1 and S2 are both blocks of memory with
+ nonzero sizes, and the last byte in each block must be a null byte.
+ Report an error and exit if there is an error. */