add in-line doc

Brian Warner had the idea of "forgetfulness oriented programming".  Anything that you can't remember six months later needs to be simplified or documented.  This weird little stanza that I inherited from Luigi Rizzo's library is in that class.

darcs-hash:a84e7a80dd6fa2541254120e377cf2a87b0e235b

diff --git a/zfec/zfec/_fecmodule.c b/zfec/zfec/_fecmodule.c
index 38fc4004cb8f67402bce85c67f4540778ed66753..05b24d67a33c9a546bd8705dc485f90228c52b28 100644 (file)
--- a/zfec/zfec/_fecmodule.c
+++ b/zfec/zfec/_fecmodule.c
@@ -429,7 +429,9 @@ Decoder_decode(Decoder *self, PyObject *args) {
         oldsz = sz;
     }
 
-    /* move src packets into position */
+    /* Move src packets into position.  At the end of this loop we want the i'th
+       element of the arrays to be the block with block number i, if that block
+       is among our inputs. */
     for (i=0; i<self->kk;) {
         if (cblocknums[i] >= self->kk || cblocknums[i] == i)
             i++;