--- a/liblrzip.c
+++ b/liblrzip.c
@@ -36,7 +36,7 @@
 #include "lrzip_core.h"
 #include "rzip.h"
 
-#if defined(__APPLE__) || defined(__FreeBSD__)
+#if defined(__APPLE__) || defined(__FreeBSD__) || defined(__sun) || defined(sun)
 # define fmemopen(s, len, modes) fake_fmemopen((s), (len), (modes))
 static FILE *fake_fmemopen(void *buf, size_t buflen, const char *mode)
 {