anchor.diff:  FROM ubuntu:xenial
   
  -ENV OPENRESTY_VERSION 1.11.2.1
  -ENV PATH $PATH:/opt/stapxx-master:/opt/stapxx-master/samples:/opt/FlameGraph-master
  +ENV OPENRESTY_VERSION 1.11.2.2
  +ENV PATH $PATH:/opt/stapxx-master:/opt/stapxx-master/samples:/opt/FlameGraph-master:/opt/openresty-systemtap-toolkit-master
   ENV DEBIAN_FRONTEND noniteractive
   
   RUN apt-get update && \
  
positive.code:     mkdir -p /srv/nginx/logs && \
      ln -s /usr/local/openresty/nginx/sbin/nginx /usr/local/bin && \
      ln -sf /dev/stdout /srv/nginx/logs/access.log && \
      ln -sf /dev/stderr /srv/nginx/logs/error.log
  
  WORKDIR /srv
  
  
negative.code:         build-essential && \
      curl -OL https://github.com/openresty/stapxx/archive/master.zip && \
      curl -o FlameGraph.zip -L https://github.com/brendangregg/FlameGraph/archive/master.zip && \
      curl -o openresty-systemtap-toolkit.zip -L https://github.com/openresty/openresty-systemtap-toolkit/archive/master.zip && \
      unzip master.zip -d /opt && \
      unzip FlameGraph.zip -d /opt && \
      unzip openresty-systemtap-toolkit.zip -d /opt && \
      rm master.zip && \
      curl -O https://openresty.org/download/openresty-${OPENRESTY_VERSION}.tar.gz && \
      curl -O https://openresty.org/download/openresty-${OPENRESTY_VERSION}.tar.gz.asc && \
  