Fixed missing include.

src/net/linux/socket_startup.cpp

@@ -22,9 +22,10 @@
 
 #include <net/socket_startup.h>
 
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <netinet/in.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <unistd.h>
 
 bool
 socket_startup()
@@ -37,18 +38,18 @@ socket_cleanup()
 {
 }
 
-bool
-socket_has_sctp()
-{
-#ifdef IPPROTO_SCTP
-	int test = socket(AF_INET, SOCK_STREAM, IPPROTO_SCTP);
-
-	if (test == -1)
-		return false;
-	close(test);
-	return true;
-#else
-	return false;
-#endif
-}
+bool
+socket_has_sctp()
+{
+#ifdef IPPROTO_SCTP
+	int test = socket(AF_INET, SOCK_STREAM, IPPROTO_SCTP);
+
+	if (test == -1)
+		return false;
+	close(test);
+	return true;
+#else
+	return false;
+#endif
+}