doc: protocol

Signed-off-by: Mattias Andrée <maandree@operamail.com>

1 files changed, 33 insertions, 0 deletions

diff --git a/doc/protocol b/doc/protocol
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index 0000000..bdff6ac
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+init:
+	Select a filename.
+
+	Create XSI semaphore array {S = 0, W = 0, X = 1 and Q = 0}
+	with random key. Store the semaphore array's key in
+	decimal form on the first line in the selected file.
+
+	Create XSI shared memory, with an allocation of 2048 bytes,
+	with a random key. Store the shared memory's key in
+	decimal form on the second line in the selected file.
+
+
+broadcast:
+	with P(X):
+	  Z(W)
+	  Write NUL-terminate message to shared memory
+	  Q := 0
+	  Z(S)
+
+
+listen:
+	V(S) with undo on exit
+	forever:
+	  V(Q)
+	  Z(Q)
+	  Read NUL-terminated message from shared memory
+	  if breaking:
+	    P(S) with undo on exit
+	    break
+	  with V(W):
+	    with P(S):
+	       Z(S)
+