Squash commits for public release

userland/tests/sigtest/BUILD.gn

@@ -0,0 +1,8 @@
+import("//build/userland/TEMPLATE.gni")
+
+xOS_executable("sigtest") {
+  install_path = "bin/"
+  sources = [ "main.c" ]
+  configs = [ "//build/userland:userland_flags" ]
+  deplibs = [ "libc" ]
+}

userland/tests/sigtest/main.c

@@ -0,0 +1,20 @@
+#include <fcntl.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+void save_on_terminate()
+{
+    printf("Saving file and exiting");
+    fflush(stdout);
+}
+
+int main(int argc, char** argv)
+{
+    sigaction(SIGTERM, save_on_terminate);
+    while (1) {
+        // infinite loop
+    }
+    return 0;
+}