diff --git a/integrations/README.md b/integrations/README.md
index ff55286..6881c23 100644
--- a/integrations/README.md
+++ b/integrations/README.md
@@ -14,19 +14,19 @@ For more support on these integrations, or if you'd like help creating a new int
 ***
 ## Build flags
 
-`SDK_DEBUG` - Turns on SDK activity/warning/error output. Levels of verbosity can be adjusted in `src/SDK_Debug.h`
+- `SDK_DEBUG` - Turns on SDK activity/warning/error output. Levels of verbosity can be adjusted in `src/SDK_Debug.h`
 
-`SDK_DEBUG_LOGFILE` - Used in conjunction with `SDK_DEBUG`, this will write all SDK debug chatter to a log file. To use this, set `make SDK_DEBUG_LOGFILE=1` then `export ZT_SDK_LOGFILE=debug.log`. 
+- `SDK_DEBUG_LOGFILE` - Used in conjunction with `SDK_DEBUG`, this will write all SDK debug chatter to a log file. To use this, set `make SDK_DEBUG_LOGFILE=1` then `export ZT_SDK_LOGFILE=debug.log`. 
 
-`SDK_LWIP_DEBUG` - Turns on debug output for the lwIP library.
+- `SDK_LWIP_DEBUG` - Turns on debug output for the lwIP library.
 
-`SDK_BUNDLED` - Builds the SDK as a single target including an API shim, the lwIP library, and the ZeroTier service.
+- `SDK_BUNDLED` - Builds the SDK as a single target including an API shim, the lwIP library, and the ZeroTier service.
 
-`SDK_SERVICE`
+- `SDK_SERVICE`
 
-`SDK_SOCKS_PROXY` - Enables the SOCK5 Proxy. 
+- `SDK_SOCKS_PROXY` - Enables the SOCK5 Proxy. 
 
-`SDK_UNITY_3D` - For use when building a target for a native plugin for Unity3D.
+- `SDK_UNITY_3D` - For use when building a target for a native plugin for Unity3D.
 
 
 ***
diff --git a/src/SDK_Debug.c b/src/SDK_Debug.c
index 4640911..7162cf0 100644
--- a/src/SDK_Debug.c
+++ b/src/SDK_Debug.c
@@ -78,6 +78,7 @@ void dwr(int level, const char *fmt, ... )
     }
     if(debug_logfile) {
       FILE *file = fopen(debug_logfile,"a");
+      fprintf(file, "%s [tid=%7d] ", timestring, tid);
       vfprintf(file, fmt, ap);
       fclose(file);
       va_end(ap);
diff --git a/src/SDK_Intercept.c b/src/SDK_Intercept.c
index 150fae0..7679abd 100644
--- a/src/SDK_Intercept.c
+++ b/src/SDK_Intercept.c
@@ -527,7 +527,7 @@ char *api_netpath;
         if(!check_intercept_enabled_for_thread()) { 
             return realclose(fd);
         }
-        zt_close(fd);
+        return zt_close(fd);
     }
 
     // ------------------------------------------------------------------------------
@@ -550,7 +550,6 @@ char *api_netpath;
         return zt_getsockname(sockfd, addr, addrlen);
     }
 
-
     // ------------------------------------------------------------------------------
     // ------------------------------------ syscall() -------------------------------
     // ------------------------------------------------------------------------------
diff --git a/tests/udp_client.c b/tests/udp_client.c
index 992fac5..e3f5c22 100755
--- a/tests/udp_client.c
+++ b/tests/udp_client.c
@@ -14,10 +14,7 @@ int main(int argc, char * argv[])
         printf("usage: udp_client <port>\n");
         return 0;
     }
-
     int port = atoi(argv[1]);
-
-    printf("cpp_udp_socket_client_test():\n");
     ssize_t n_sent;
     int sock = -1;
     struct sockaddr_in server;
@@ -29,7 +26,7 @@ int main(int argc, char * argv[])
             return 1;
         }
     }
-    server.sin_addr.s_addr = inet_addr("10.5.5.2");
+    server.sin_addr.s_addr = inet_addr("10.5.5.47");
     server.sin_family = AF_INET;
     server.sin_port = htons(port);
     
@@ -41,9 +38,7 @@ int main(int argc, char * argv[])
         return 1;    
 	}
 
-    //return 1;
-
-    // Send multiple UDP datagrams to server
+    // TX
     char data[1024];
     memset(data, 0, sizeof(data));
     int count = 0;
diff --git a/tests/udp_server.c b/tests/udp_server.c
index 113813d..e9f8614 100755
--- a/tests/udp_server.c
+++ b/tests/udp_server.c
@@ -1,17 +1,13 @@
 // UDP Server test program
 
-#include <stdio.h>      /* standard C i/o facilities */
-#include <stdlib.h>     /* needed for atoi() */
-#include <unistd.h>     /* defines STDIN_FILENO, system calls,etc */
-#include <sys/types.h>  /* system data type definitions */
-#include <sys/socket.h> /* socket specific definitions */
-#include <netinet/in.h> /* INET constants and stuff */
-#include <arpa/inet.h>  /* IP address conversion stuff */
-#include <netdb.h>      /* gethostbyname */
-
-
-
-/* this routine echos any messages (UDP datagrams) received */
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h> 
+#include <arpa/inet.h>
+#include <netdb.h>
 
 #define MAXBUF 1024*1024
 
@@ -19,10 +15,6 @@ void echo( int sd ) {
   int len,n;
   char bufin[MAXBUF];
   struct sockaddr_in remote;
-
-  /* need to know how big address struct is, len must be set before the
-     call to recvfrom!!! */
-
   len = sizeof(remote);
   long count = 0;