+#include <stdlib.h> /* exit, realloc, free, atoi */
+#include <string.h> /* strchr, strdup, strlen, strncpy, strpbrk, strrchr, strstr, strspn,
+ strcasecmp, strcmp, strncmp, strerror, memcpy, memmove, memset */
+#include <stdio.h> /* fflush, fopen, fprintf, printf, snprintf, sscanf, vfprintf, vprintf, vsnprintf */
+#include <time.h> /* gmtime, localtime, mktime, strftime, time */
+#include <math.h> /* cos, sin */
+#include <netinet/in.h> /* struct in_addr */
+#include <GLES2/gl2.h> /* glXXX */