diff --git a/streamApp/tests/testDouble b/streamApp/tests/testDouble
new file mode 100755
index 0000000..7a6fa14
--- /dev/null
+++ b/streamApp/tests/testDouble
@@ -0,0 +1,121 @@
+#!/usr/bin/env tclsh
+source streamtestlib.tcl
+
+# Define records, protocol and startup (text goes to files)
+# The asynPort "device" is connected to a network TCP socket
+# Talk to the socket with send/receive/assure
+# Send commands to the ioc shell with ioccmd
+
+set records {
+    record (ai, "DZ:test1")
+    {
+        field (DTYP, "stream")
+        field (INP,  "@test.proto test1 device")
+    }
+    record (ai, "DZ:test2")
+    {
+        field (DTYP, "stream")
+        field (INP,  "@test.proto test2 device")
+    }
+    record (ai, "DZ:test3")
+    {
+        field (DTYP, "stream")
+        field (INP,  "@test.proto test3 device")
+    }
+    record (ai, "DZ:test4")
+    {
+        field (DTYP, "stream")
+        field (INP,  "@test.proto test4 device")
+    }
+}
+
+set protocol {
+    Terminator = LF;
+    @mismatch {out "mismatch";}
+    test1 {in "%f"; out "|%f|%10f|%.2f|%- 10.5f|% f|%+f|%-5.1f|%#f|"; }
+    test2 {in "%6f%(DESC)s"; out "|%g|%(DESC)s|"; }
+    test3 {in "% 6f%(DESC)s"; out "|%g|%(DESC)s|"; }
+    test4 {in "%#f"; out "%f"; }
+}
+
+set startup {
+}
+
+set debug 0
+
+startioc
+
+ioccmd {dbpf DZ:test1.PROC 1}
+send "3.14159265359\n"
+assure "|3.141593|  3.141593|3.14| 3.14159  | 3.141593|+3.141593|3.1  |3.141593|\n"
+ioccmd {dbpf DZ:test1.PROC 1}
+send "-3.14159265359\n"
+assure "|-3.141593| -3.141593|-3.14|-3.14159  |-3.141593|-3.141593|-3.1 |-3.141593|\n"
+ioccmd {dbpf DZ:test1.PROC 1}
+send "0\n"
+assure "|0.000000|  0.000000|0.00| 0.00000  | 0.000000|+0.000000|0.0  |0.000000|\n"
+ioccmd {dbpf DZ:test1.PROC 1}
+send "NAN\n"
+assure "|nan|       nan|nan| nan      | nan|+nan|nan  |nan|\n"
+ioccmd {dbpf DZ:test1.PROC 1}
+send "-Inf\n"
+assure "|-inf|      -inf|-inf|-inf      |-inf|-inf|-inf |-inf|\n"
+ioccmd {dbpf DZ:test1.PROC 1}
+send "1e6\n"
+assure "|1000000.000000|1000000.000000|1000000.00| 1000000.00000| 1000000.000000|+1000000.000000|1000000.0|1000000.000000|\n"
+ioccmd {dbpf DZ:test1.PROC 1}
+send "   -  3.14159265359\n"
+assure "mismatch\n"
+ioccmd {dbpf DZ:test1.PROC 1}
+send "bla\n"
+assure "mismatch\n"
+ioccmd {dbpf DZ:test1.PROC 1}
+send "  bla\n"
+assure "mismatch\n"
+ioccmd {dbpf DZ:test1.PROC 1}
+send "-bla\n"
+assure "mismatch\n"
+
+ioccmd {dbpf DZ:test2.PROC 1}
+send "3.14159265359\n"
+assure "|3.1415|9265359|\n"
+ioccmd {dbpf DZ:test2.PROC 1}
+send "     3.14159265359\n"
+assure "|3.1415|9265359|\n"
+ioccmd {dbpf DZ:test2.PROC 1}
+send "  10blabla\n"
+assure "|10|blabla|\n"
+ioccmd {dbpf DZ:test2.PROC 1}
+send "  1\n"
+assure "|1||\n"
+
+ioccmd {dbpf DZ:test3.PROC 1}
+send "3.14159265359\n"
+assure "|3.1415|9265359|\n"
+ioccmd {dbpf DZ:test3.PROC 1}
+send "     3.14159265359\n"
+assure "|3|.14159265359|\n"
+ioccmd {dbpf DZ:test3.PROC 1}
+send "  10blabla\n"
+assure "|10|blabla|\n"
+ioccmd {dbpf DZ:test3.PROC 1}
+send "  1\n"
+assure "|1||\n"
+
+ioccmd {dbpf DZ:test4.PROC 1}
+send "3.14159265359\n"
+assure "3.141593\n"
+ioccmd {dbpf DZ:test4.PROC 1}
+send "     -3.14159265359\n"
+assure "-3.141593\n"
+ioccmd {dbpf DZ:test4.PROC 1}
+send "   -  3.14159265359\n"
+assure "-3.141593\n"
+ioccmd {dbpf DZ:test4.PROC 1}
+send "   +  3.14159265359\n"
+assure "3.141593\n"
+ioccmd {dbpf DZ:test4.PROC 1}
+send "   +-  3.14159265359\n"
+assure "mismatch\n"
+
+finish