Stale write event may happen if epoll_wait() reported both read and write
events, and processing of the read event closed descriptor.
Patch by Yichun Zhang (agentzh).
The default value is 32 AIO simultaneous requests per worker. Previously
they were hardcoded to 1024, and it was too large, since Linux allocated
them early on io_setup(), but not on request itself. So with default value
of /proc/sys/fs/aio-max-nr equal to 65536 only 64 worker processes could
be run simultaneously. 32 AIO requests are enough for modern disks even if
server runs only 1 worker.
syscall(2) uses usual libc convention, it returns -1 on error and
sets errno. Obsolete _syscall(2) returns negative value of error.
Thanks to Hagai Avrahami.
*) Feature: the "stub" parameter in the "include" SSI command.
*) Feature: the "block" SSI command.
*) Feature: the unicode2nginx script was added to contrib.
*) Bugfix: if a "root" was specified by variable only, then the root
was relative to a server prefix.
*) Bugfix: if the request contained "//" or "/./" and escaped symbols
after them, then the proxied request was sent unescaped.
*) Bugfix: the $r->headers_in("Cookie") of the ngx_http_perl_module now
returns all "Cookie" header lines.
*) Bugfix: a segmentation fault occurred if
"client_body_in_file_only on" was used and nginx switched to a next
upstream.
*) Bugfix: on some condition while reconfiguration character codes
inside the "charset_map" may be treated invalid; the bug had
appeared in 0.3.50.
*) Change: the "add_header" directive adds the string to 204, 301, and
302 responses.
*) Feature: the "server" directive in the "upstream" context supports
the "weight" parameter.
*) Feature: the "server_name" directive supports the "*" wildcard.
*) Feature: nginx supports the request body size more than 2G.
*) Bugfix: if a client was successfully authorized using "satisfy_any
on", then anyway the message "access forbidden by rule" was written
in the log.
*) Bugfix: the "PUT" method may erroneously not create a file and
return the 409 code.
*) Bugfix: if the IMAP/POP3 backend returned an error, then nginx
continued proxying anyway.
*) Feature: the "http_503" parameter of the "proxy_next_upstream" or
"fastcgi_next_upstream" directives.
*) Bugfix: ngx_http_perl_module did not work with inlined in the
configuration code, if it was not started with the "sub" word.
*) Bugfix: in the "post_action" directive.
