1 files changed, 12 insertions, 0 deletions
diff --git a/code/snippets/cow.rb b/code/snippets/cow.rb
new file mode 100644
index 0000000..f7d85d4
--- /dev/null
+++ b/code/snippets/cow.rb
@@ -0,0 +1,12 @@
+arr = [1,2,3]
+
+fork do
+  # At this point the child process has been initialized.
+  # Because of CoW the arr variable hasn't been copied yet.
+  arr << 4
+  # The above line of code modifies the array, so a copy of
+  # the array will need to be made for this process before
+  # it can modify it. The array in the parent process remains
+  # unchanged.
+end
+