Add 1998/df/try.sh

This script runs repeatedly until (when prompted) one hits 'q' (or 'Q')
or else sends ctrl-c/intr. I also added a question to the extra credit
questions: are there any misspelt words and if there are what are they?
I also added that there's a way to cheat very easily but I did not say
how to do it. It should be pretty obvious how to do it to anyone who
tries the program once or if not once a few times.

1998/df/try.sh

@@ -0,0 +1,25 @@
+#!/usr/bin/env bash
+# 
+# try.sh - demonstrate IOCCC winner 1998/df
+#
+
+# make sure CC is set so that when we do make CC="$CC" it isn't empty. Doing it
+# this way allows us to have the user specify a different compiler in an easy
+# way.
+if [[ -z "$CC" ]]; then
+    CC="cc"
+fi
+
+make CC="$CC" all >/dev/null || exit 1
+
+# clear screen after compilation so that only the entry is shown
+clear
+
+while [[ 1 ]]; do
+    read -r -n 1 -p "Press any key to run ./df or 'q' to quit: "
+    echo 1>&2
+    if [[ "$REPLY" = "q" || "$REPLY" = "Q" ]]; then
+	exit 0
+    fi
+    ./df
+done