How to change the nginx configure file(Resolved)?

[swish]

In Tiny Core Linux 3.4,I install a nginx,but I can't change the configure file.When I try edit /usr/local/conf/nginx.conf and save it ,A error message:
  Error writing to file 'nginx.conf':
  Read-only file system.
  So,what's can I do next?How to change the configure file?

[gerald_clark]

cd /usr/local/conf
mv nginx.conf nginx.conf.org
cp nginx.conf.org nginx.conf

echo "usr/local/conf/nginx.conf" >> /opt/.filetool.lst

[swish]

 ;)Very Very thank you.It's OK!