diff --git a/renderdoc/os/os_specific.cpp b/renderdoc/os/os_specific.cpp
index 633eca903..5981a3aae 100644
--- a/renderdoc/os/os_specific.cpp
+++ b/renderdoc/os/os_specific.cpp
@@ -202,8 +202,20 @@ TEST_CASE("Test OS-specific functions", "[osspecific]")
   SECTION("OpenTransientFileHandle")
   {
     rdcstr filename = FileIO::GetTempFolderFilename() + "/rdcunittestfile";
+    INFO(filename);
     FILE *f = FileIO::OpenTransientFileHandle(filename, FileIO::OverwriteBinary);
-    CHECK(FileIO::exists(filename));
+    CHECK(f);
+
+    uint32_t magic = 0xdeadbeef;
+    FileIO::fwrite(&magic, sizeof(uint32_t), 1, f);
+
+    uint32_t readback = 0;
+    FileIO::fseek64(f, 0, SEEK_SET);
+
+    FileIO::fread(&readback, sizeof(uint32_t), 1, f);
+
+    CHECK(magic == readback);
+
     FileIO::fclose(f);
     CHECK_FALSE(FileIO::exists(filename));
   }