diff --git a/scsh/syscalls1.c b/scsh/syscalls1.c
index 2f5f0b5..1b882a6 100644
--- a/scsh/syscalls1.c
+++ b/scsh/syscalls1.c
@@ -531,7 +531,7 @@ s48_value scsh_close(s48_value sch_fdes)
   int retval = close (s48_extract_fixnum (sch_fdes));
   if (retval == 0)
     return S48_TRUE;
-  else if (retval == EBADF)
+  else if (errno == EBADF)
     return S48_FALSE;
   else s48_raise_os_error_1 (errno, sch_fdes);
 }