From 2ccd8a60cb415d20ba3dcfc6ce00a7c602d3aa8b Mon Sep 17 00:00:00 2001
From: luis <luis@e0a8ed71-7df4-0310-8962-fdc924857419>
Date: Tue, 26 Jul 2011 12:03:40 +0000
Subject: [PATCH] Add doc for get_initial_ttl_guess()

---
 osscan2.cc | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/osscan2.cc b/osscan2.cc
index 6d69916e0..01a675024 100644
--- a/osscan2.cc
+++ b/osscan2.cc
@@ -188,6 +188,11 @@ static struct AVal *make_aval_ipid_seq(struct AVal *av, const char *attribute,
 }
 
 
+/* Returns a guess about the original TTL based on an observed TTL value.
+ * This function assumes that the target from which we received the packet was
+ * less than 32 hops away. Also, note that although some systems use an
+ * initial TTL of 60, this function rounds that to 64, as both values
+ * cannot be reliably distinguished based on a simple observed hop count. */
 int get_initial_ttl_guess(u8 ttl) {
   if (ttl <= 32)
     return 32;