diff --git a/src/ioslaves/file/ConfigureChecks.cmake b/src/ioslaves/file/ConfigureChecks.cmake
--- a/src/ioslaves/file/ConfigureChecks.cmake
+++ b/src/ioslaves/file/ConfigureChecks.cmake
@@ -7,6 +7,7 @@
 check_include_files(sys/time.h    HAVE_SYS_TIME_H)
 check_include_files(string.h      HAVE_STRING_H)
 check_include_files(limits.h      HAVE_LIMITS_H)
+check_function_exists(sendfile    HAVE_SENDFILE)
 
 check_function_exists(posix_fadvise    HAVE_FADVISE)                  # kioslave
 
diff --git a/src/ioslaves/file/config-kioslave-file.h.cmake b/src/ioslaves/file/config-kioslave-file.h.cmake
--- a/src/ioslaves/file/config-kioslave-file.h.cmake
+++ b/src/ioslaves/file/config-kioslave-file.h.cmake
@@ -13,3 +13,5 @@
 /* Defined if system has extended file attributes support. */
 #cmakedefine01 HAVE_SYS_XATTR_H
 
+/* Defined if system has the sendfile function. */
+#cmakedefine01 HAVE_SENDFILE
diff --git a/src/ioslaves/file/file_unix.cpp b/src/ioslaves/file/file_unix.cpp
--- a/src/ioslaves/file/file_unix.cpp
+++ b/src/ioslaves/file/file_unix.cpp
@@ -49,7 +49,7 @@
 #include "fdreceiver.h"
 
 //sendfile has different semantics in different platforms
-#if defined HAVE_SENDFILE && defined Q_OS_LINUX
+#if HAVE_SENDFILE && defined Q_OS_LINUX
 #define USE_SENDFILE 1
 #endif