Initial project import

tools/v/vlib/os/signal_default.c.v

@@ -0,0 +1,21 @@
+@[has_globals]
+module os
+
+#flag -lpthread
+
+fn C.pthread_self() usize
+
+// g_main_thread_id and is_main_thread can be used to determine if the current thread is the main thread.
+// if need to get the tid of the main thread, can use the global variable g_main_thread_id
+// instead of using thread_id() every time.
+__global g_main_thread_id = u64(C.pthread_self())
+
+// is_main_thread returns whether the current thread is the main thread.
+pub fn is_main_thread() bool {
+	return g_main_thread_id == u64(C.pthread_self())
+}
+
+fn signal_ignore_internal(_ ...Signal) {
+	// just do nothing by default, since that is most portable ¯\_(ツ)_/¯,
+	// especially on platforms like OpenBSD etc
+}