memory-search: use uuid for cookie instead of manual /dev/urandom

src/bin/memory-search.rs

@@ -150,11 +150,7 @@ fn load_or_create_cookie(dir: &Path, session_id: &str) -> String {
 }
 
 fn generate_cookie() -> String {
-    let mut buf = [0u8; 12];
-    fs::File::open("/dev/urandom")
-        .and_then(|mut f| io::Read::read_exact(&mut f, &mut buf))
-        .expect("failed to read urandom");
-    buf.iter().map(|b| format!("{:02x}", b)).collect()
+    uuid::Uuid::new_v4().as_simple().to_string()[..12].to_string()
 }
 
 fn load_seen(dir: &Path, session_id: &str) -> HashSet<String> {