diff --git a/Makefile b/Makefile
index ebd663e..9d1bfb0 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,6 @@
 TARGET = ciadpi
 CC ?= gcc
-CFLAGS += -std=c99 -O2
+CFLAGS += -std=c99 -O2 -D_XOPEN_SOURCE=500 
 SOURCES = packets.c main.c conev.c proxy.c desync.c
 
 all:
diff --git a/desync.c b/desync.c
index 361812c..a966791 100644
--- a/desync.c
+++ b/desync.c
@@ -1,5 +1,8 @@
 #include <stdio.h>
+#include <string.h>
 #include <unistd.h>
+#include <time.h>
+#include <sys/time.h>
 #include <sys/socket.h>
 #include <arpa/inet.h>
 #include <netinet/tcp.h>
@@ -57,7 +60,10 @@ int fake_attack(int sfd, char *buffer, ssize_t n, int cnt, int pos)
             perror("sendfile");
             break;
         }
-        usleep(params.sfdelay);
+        struct timespec delay = { 
+            .tv_nsec = params.sfdelay * 1000
+        };
+        nanosleep(&delay, 0);
         memcpy(p, buffer, pos);
         
         if (setsockopt(sfd, IPPROTO_IP, IP_TTL,
diff --git a/main.c b/main.c
index 215d550..0c941d7 100644
--- a/main.c
+++ b/main.c
@@ -341,7 +341,7 @@ int main(int argc, char **argv)
             
         case 'w': //
             params.sfdelay = strtoul(optarg, &end, 0);
-            if (optarg == end || *end)
+            if (optarg == end || params.sfdelay > 1000000 || *end)
                 invalid = 1;
             break;
             
diff --git a/params.h b/params.h
index e07b9ae..6f86985 100644
--- a/params.h
+++ b/params.h
@@ -47,4 +47,4 @@ extern struct packet fake_http;
 #define LOG_L 2
 
 #define LOG(s, str, ...) \
-    if (params.debug >= s) printf(str, ##__VA_ARGS__)
\ No newline at end of file
+    if (params.debug >= s) printf(str, ##__VA_ARGS__)