auto import from //depot/cupcake/@135843
diff --git a/send-ack.awk b/send-ack.awk
new file mode 100644
index 0000000..f55b7c2
--- /dev/null
+++ b/send-ack.awk
@@ -0,0 +1,68 @@
+BEGIN {
+ # we need the number of bytes in a packet to do the output
+ # in packet numbers rather than byte numbers.
+ if (packetsize <= 0)
+ packetsize = 512
+ expectNext = 1
+ lastwin = -1
+ }
+ {
+ # convert tcp trace to send/ack form.
+ n = split ($1,t,":")
+ tim = t[1]*3600 + t[2]*60 + t[3]
+ if (NR <= 1) {
+ tzero = tim
+ ltim = tim
+ OFS = "\t"
+ }
+ if ($6 != "ack") {
+ # we have a data packet record:
+ # ignore guys with syn, fin or reset 'cause we
+ # can't handle their sequence numbers. Try to
+ # detect and add a flag character for 'anomalies':
+ # * -> re-sent packet
+ # - -> packet after hole (missing packet(s))
+ # # -> odd size packet
+ if ($5 !~ /[SFR]/) {
+ i = index($6,":")
+ j = index($6,"(")
+ strtSeq = substr($6,1,i-1)
+ endSeq = substr($6,i+1,j-i-1)
+ len = endSeq - strtSeq
+ id = endSeq
+ if (! timeOf[id])
+ timeOf[id] = tim
+ if (endSeq - expectNext < 0)
+ flag = "*"
+ else {
+ if (strtSeq - expectNext > 0)
+ flag = "-"
+ else if (len != packetsize)
+ flag = "#"
+ else
+ flag = " "
+ expectNext = endSeq
+ }
+ printf "%7.2f\t%7.2f\t%s send %s %d", tim-tzero, tim-ltim,\
+ flag, $5, strtSeq
+ if (++timesSent[id] > 1)
+ printf " (%.2f) [%d]", tim - timeOf[id], timesSent[id]
+ if (len != packetsize)
+ printf " <%d>", len
+ }
+ } else {
+ id = $7
+
+ printf "%7.2f\t%7.2f\t%s ack %s %d", tim-tzero, tim-ltim,\
+ flag, $5, id
+ if ($9 != lastwin) {
+ printf " win %d", $9
+ lastwin = $9
+ }
+ printf " (%.2f)", tim - timeOf[id]
+ if (++timesAcked[id] > 1)
+ printf " [%d]", timesAcked[id]
+ }
+ printf "\n"
+ ltim = tim
+ }