another example to deal with multi spawned processes

examples/multi-spawn.sh

@@ -0,0 +1,42 @@
+#!/usr/bin/env bash
+
+bashexp() { sexpect -s /tmp/sexpect-bash-$$.sock "$@"; }
+pythexp() { sexpect -s /tmp/sexpect-pyth-$$.sock "$@"; }
+
+ps1bash='bash-[0-9.]+[$#] $'
+ps1pyth='>>> $'
+
+bashexp spawn bash --norc
+pythexp spawn python3
+
+bashexp expect -re "$ps1bash"; echo
+pythexp expect -re "$ps1pyth"; echo
+
+sum=0
+for ((i = 1; i <= 10; ++i)); do
+    if ((i % 2)); then  # bash to add odd numbers
+        bashexp expect -lookback 1
+        bashexp send -enter "echo sum=\$(($sum + $i))"
+        bashexp expect -re 'sum=([0-9]+)'
+        sum=$( bashexp expect_out -i 1 )
+
+        bashexp expect -re "$ps1bash"; echo
+    else  # python to add even numbers
+        pythexp expect -lookback 1
+        pythexp send -enter "print('sum=%d' % ($sum + $i))"
+        pythexp expect -re 'sum=([0-9]+)'
+        sum=$( pythexp out -i 1 )
+
+        pythexp expect -re "$ps1pyth"; echo
+    fi
+done
+
+bashexp expect -lookback 1
+bashexp send -enter 'exit # Bash exiting ...'
+bashexp wait
+
+pythexp expect -lookback 1
+pythexp send -enter 'exit() # Python exiting ...'
+pythexp wait
+
+echo "---- Final sum: $sum ----"