diff --git a/src/pv/transfer.c b/src/pv/transfer.c
index d989eb9..a463d5d 100644
--- a/src/pv/transfer.c
+++ b/src/pv/transfer.c
@@ -294,6 +294,7 @@ static ssize_t pv__transfer_write_repeated(int fd, char *buf, size_t count, bool
 	return total_written;
 }
 
+/* TODO: make pv__transfer_read() return a boolean, for easier understanding. */
 
 /*
  * Read some data from the given file descriptor, updating the state.
@@ -632,6 +633,9 @@ static int pv__transfer_read(pvstate_t state, int fd, bool *eof_in, bool *eof_ou
 }
 
 
+/* TODO: make pv__transfer_write() return a boolean, for easier understanding. */
+
+
 /*
  * Write state->transfer.to_write bytes of data from the transfer buffer to the output.
  *