1 files changed, 1 insertions, 1 deletions

diff --git a/arch/um/os-Linux/file.c b/arch/um/os-Linux/file.c
index 3bd10deea280..09251338d99e 100644
--- a/arch/um/os-Linux/file.c
+++ b/arch/um/os-Linux/file.c
@@ -171,7 +171,7 @@ int os_sigio_async(int master, int slave)
 
         flags = fcntl(master, F_GETFL);
         if(flags < 0)
-                return errno;
+                return -errno;
 
         if((fcntl(master, F_SETFL, flags | O_NONBLOCK | O_ASYNC) < 0) ||
            (fcntl(master, F_SETOWN, os_getpid()) < 0))