diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9de6aba..76351c1 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -158,7 +158,7 @@
 check_symbol_exists(gettimeofday sys/time.h HAVE_GETTIMEOFDAY)
 check_symbol_exists(basename libgen.h HAVE_BASENAME)
 check_symbol_exists(chsize io.h HAVE_CHSIZE)
-check_symbol_exists(daemon stdlib.h HAVE_DAEMON)
+check_symbol_exists(daemon "unistd.h;stdlib.h" HAVE_DAEMON)
 check_symbol_exists(dirname libgen.h HAVE_DIRNAME)
 check_symbol_exists(getrlimit sys/resource.h HAVE_GETRLIMIT)
 check_symbol_exists(mlockall sys/mman.h HAVE_MLOCKALL)