diff --git a/adb_utils.h b/adb_utils.h
index b9da980..537d0e4 100644
--- a/adb_utils.h
+++ b/adb_utils.h
@@ -46,4 +46,6 @@
 
 std::string perror_str(const char* msg);
 
+bool set_file_block_mode(int fd, bool block);
+
 #endif