Add information in README about signalling.

diff --git a/README b/README
index f1bb2fa33be02ac79b7b4a1d5ef3a9497cf78303..32d553784742787128a45778879e6f42c475090a 100644 (file)
--- a/README
+++ b/README
@@ -38,3 +38,20 @@ If process creation was completed without errors, you should see following outpu
 [process2] Calculated: 10 characters. Sending...
 [process3] Fetched: 4 bytes
 [process3] Process2 send: 10
+
+Signalling
+==========
+
+After bootstrapping processes, you can send them signals.
+Processes registers custom handlers for following ones:
+- SIGUSR1 (User defined signal 1) - used for internal purposes. Signal must be
+  sent in pair with message queue.
+- SIGTERM (Terminated) - additionaly to standard behaviour, this signal allows
+  releasing aquired resources and notify other processes using SIGUSR1 to do the
+  same.
+- SIGTSTP (Stopped) - additionaly to standard behaviour, this signal allows
+  holding aquired resources (closes pipes for example), and notify other
+  processes using SIGUSR1 to do the same.
+- SIGCONT (Continued) - aditionaly to standard behaviour, this signal allows
+  resume process working by opening closed pipes, and notify other processes
+  using SIGUSR1 to do the same.