changes in tmp dir

tmp/uuid.cpp

@@ -0,0 +1,34 @@
+
+// https://mariusbancila.ro/blog/2018/02/27/stduuid-a-cpp-library-for-universally-unique-identifiers/
+
+
+// #pragma once
+
+#include <string>
+#include <random>
+#include <iostream>
+
+std::string get_uuid() {
+    static std::random_device dev;
+    static std::mt19937_64 rng(dev());
+
+    std::uniform_int_distribution<int> dist(0, 15);
+    const char *v = "0123456789abcdef";
+    const bool dash[] = { 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0 };
+
+    std::string res;
+    res.reserve(40);
+    for (int i = 0; i < 16; i++) {
+        if (dash[i]) res += "-";
+        res += v[dist(rng)];
+        res += v[dist(rng)];
+    }
+    return res;
+}
+
+// g++ uuid_test.cpp
+int main() {
+        auto uuid_str = get_uuid();
+
+        std::cout << uuid_str << std::endl;
+}