nginx 0.2.0 *) The pid-file names used during online upgrade was changed and now is not required a manual rename operation. The old master process adds the ".oldbin" suffix to its pid-file and executes a new binary file. The new master process creates usual pid-file without the ".newbin" suffix. If the master process exits, then old master process renames back its pid-file with the ".oldbin" suffix to the pid-file without suffix. *) Change: the "worker_connections" directive, new name of the "connections" directive; now the directive specifies maximum number of connections, but not maximum socket descriptor number. *) Feature: SSL supports the session cache inside one worker process. *) Feature: the "satisfy_any" directive. *) Change: the ngx_http_access_module and ngx_http_auth_basic_module do not run for subrequests. *) Feature: the "worker_rlimit_nofile" and "worker_rlimit_sigpending" directives. *) Bugfix: if all backend using in load-balancing failed after one error, then nginx did not try do connect to them during 60 seconds. *) Bugfix: in IMAP/POP3 command argument parsing. Thanks to Rob Mueller. *) Bugfix: errors while using SSL in IMAP/POP3 proxy. *) Bugfix: errors while using SSI and gzipping. *) Bugfix: the "Expires" and "Cache-Control" header lines were omitted from the 304 responses. Thanks to Alexandr Kukushkin.

--- a/src/os/unix/ngx_process.h
+++ b/src/os/unix/ngx_process.h
@@ -13,6 +13,8 @@
 
 typedef pid_t       ngx_pid_t;
 
+#define NGX_INVALID_PID  -1
+
 typedef void (*ngx_spawn_proc_pt) (ngx_cycle_t *cycle, void *data);
 
 typedef struct {