diff --git a/adb_utils.cpp b/adb_utils.cpp
index ca843bd..e5dc692 100644
--- a/adb_utils.cpp
+++ b/adb_utils.cpp
@@ -225,3 +225,7 @@
                << " (" << *canonical_address << ")";
     return true;
 }
+
+std::string perror_str(const char* msg) {
+    return android::base::StringPrintf("%s: %s", msg, strerror(errno));
+}