      echo "checking for OS"
 diff --git a/src/dtrace/nginx.stp b/src/dtrace/nginx.stp
 new file mode 100644
-index 0000000..a00dc40
+index 0000000..648a962
 --- /dev/null
 +++ b/src/dtrace/nginx.stp
-@@ -0,0 +1,22 @@
+@@ -0,0 +1,46 @@
++/* tapset for nginx */
++
++/* retrieve the request uri string from the ngx_http_request_t pointer */
 +function ngx_http_req_uri(r)
 +{
 +    len = @cast(r, "ngx_http_request_s", "NGX_SBIN_PATH")->uri->len

 NGX_CONF_PREFIX=`dirname $NGX_CONF_PATH`
 NGX_PID_PATH=${NGX_PID_PATH:-logs/nginx.pid}
 NGX_LOCK_PATH=${NGX_LOCK_PATH:-logs/nginx.lock}
+NGX_TAPSET_PATH=${NGX_TAPSET_PATH:-tapset/nginx.stp}
 
 if [ ".$NGX_ERROR_LOG_PATH" = ".stderr" ]; then
     NGX_ERROR_LOG_PATH=
diff --git a/auto/sources b/auto/sources
index 374ad66..70eed77 100644
--- a/auto/sources
+++ b/auto/sources
@@ -39,6 +39,11 @@ CORE_DEPS="src/core/nginx.h \

 
diff --git a/src/http/ngx_http_probe.h b/src/http/ngx_http_probe.h
new file mode 100644
index 0000000..0727968
--- /dev/null
+++ b/src/http/ngx_http_probe.h
@@ -0,0 +1,59 @@
+#ifndef _NGX_HTTP_PROBE_H_INCLUDED_
+#define _NGX_HTTP_PROBE_H_INCLUDED_
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+#include <ngx_http.h>
+
+
+#if (NGX_DTRACE)
+
+#include <ngx_dtrace_provider.h>
