diff --git a/FWCore/ParameterSet/bin/edmWriteConfigs.cpp b/FWCore/ParameterSet/bin/edmWriteConfigs.cpp
index b056ed9074eb1..715901b0a7698 100644
--- a/FWCore/ParameterSet/bin/edmWriteConfigs.cpp
+++ b/FWCore/ParameterSet/bin/edmWriteConfigs.cpp
@@ -54,6 +54,8 @@
 #include <sstream>
 #include <fstream>
 #include <filesystem>
+#include <cstdlib>
+#include <unistd.h>
 
 static char const* const kHelpOpt = "help";
 static char const* const kHelpCommandOpt = "help,h";
@@ -136,18 +138,33 @@ namespace {
     }
   }
 
-  void writeModulesFile() {
+  bool open_temp(std::string& path, std::ofstream& f) {
+    path += "/XXXXXX";
+    path += '\0';  // ensure that the string is null-terminated
+    int fd = mkstemp(path.data());
+    if (fd != -1) {
+      f.open(path.c_str(), std::ios_base::trunc | std::ios_base::out);
+      close(fd);
+      return true;
+    }
+    return false;
+  }
+
+  bool writeModulesFile() {
     if (std::filesystem::exists(std::filesystem::current_path() / "modules.py"))
       return;
-    std::array<char, L_tmpnam> buffer;
-    std::tmpnam(buffer.data());
-    std::ofstream file{buffer.data()};
-
-    file << "from FWCore.ParameterSet.ModulesProxy import _setupProxies\n"
-            "locals().update(_setupProxies(__file__))\n";
-    file.close();
-    std::filesystem::copy(buffer.data(), "modules.py");
-    std::filesystem::remove(buffer.data());
+    std::ofstream file;
+    std::string path(std::filesystem::current_path());
+    bool res = open_temp(path, file);
+    if (res) {
+      file << "from FWCore.ParameterSet.ModulesProxy import _setupProxies\n"
+              "locals().update(_setupProxies(__file__))\n";
+      file.close();
+      std::filesystem::copy(path.data(), "modules.py");
+      std::filesystem::remove(path.data());
+      return true;
+    }
+    return false;
   }
 }  // namespace
 
@@ -304,7 +321,11 @@ int main(int argc, char** argv) try {
       std::set<std::string> usedCfiFileNames;
       edm::for_all(pluginNames, std::bind(&writeCfisForPlugin, _1, factory, std::ref(usedCfiFileNames)));
       if (not pluginNames.empty()) {
-        writeModulesFile();
+        bool res = writeModulesFile();
+        if (!res) {
+          std::cerr << "writeModulesFile() failed" << std::endl;
+          return 1;
+        }
       }
     });
   } catch (cms::Exception& iException) {