- *
- * function responsible for reading one data chunk.
- *
- * \a read_chunk() must return a pointer to the next chunk of data that should
- * be sent out, or \p NULL on errors or if the end of the file was encountered.
- *
- * If it returns non-NULL, \a len must contain the length of the returned
- * buffer (which may be zero if nothing has to be sent for some reason).
- * Otherwise, \a len is used to distinguish between the eof and the error case:
- * It must be zero in the eof case, or negative if an error occcured.
-*/
-char * (*read_chunk)(long unsigned chunk_num, ssize_t *len);
+ * If the pre_select hook added one ore more file descriptors to the read or write
+ * set, this is the hook to check the result and do any I/O on those descriptors
+ * which are ready for reading/writing.
+ */
+void (*post_select)(fd_set *rfds, fd_set *wfds);
+/**
+ * each selector has its private data pointer */
+void *private_data;