2 files changed, 2 insertions, 0 deletions
diff --git a/xpread.c b/xpread.c
index 8cea02e..6fa9cfc 100644
--- a/xpread.c
+++ b/xpread.c
@@ -1,3 +1,4 @@
+#define _XOPEN_SOURCE 500	/* Needed for pread() */
 #include <errno.h>
 #include <stdlib.h>
 #include <unistd.h>
diff --git a/xpwrite.c b/xpwrite.c
index 46012b3..c6fa77a 100644
--- a/xpwrite.c
+++ b/xpwrite.c
@@ -1,3 +1,4 @@
+#define _XOPEN_SOURCE 500	/* Needed for pwrite() */
 #include <errno.h>
 #include <stdlib.h>
 #include <unistd.h>