The web server is Apache 2.2, without chroot.
I've checked the permission of /tmp, permission is 777, and I've made my CGI scripts wrote some session files in there before.
So I thought it passably not caused by permission.

In reply to Re^2: How to create sessions via FastCGI? by Ray.Zachary
in thread SOLVED: How to create sessions via FastCGI? by Ray.Zachary

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