new file mode 100644
--- /dev/null
+++ b/auto/os/features
@@ -0,0 +1,131 @@
+
+# Copyright (C) Igor Sysoev
+
+
+NGX_USER=${NGX_USER:-nobody}
+
+if [ -z "$NGX_GROUP" -a $NGX_USER = nobody ] ; then
+    if grep nobody /etc/group 2>&1 >/dev/null; then
+        echo "checking for nobody group ... found"
+        NGX_GROUP=nobody
+    else
+        echo "checking for nobody group ... not found"
+
+        if grep nogroup /etc/group 2>&1 >/dev/null; then
+            echo "checking for nogroup group ... found"
+            NGX_GROUP=nogroup
+        else 
+            echo "checking for nogroup group ... not found"
+            NGX_GROUP=nobody
+        fi
+    fi
+
+else
+    NGX_GROUP=$NGX_USER
+fi
+    
+
+ngx_feature="poll()"
+ngx_feature_name=
+ngx_feature_run=no
+ngx_feature_incs="#include <poll.h>"
+ngx_feature_libs=
+ngx_feature_test="int  n, dp; struct pollfd  pl;
+                  dp = 0; 
+                  pl.fd = 0;
+                  pl.events = 0;
+                  pl.revents = 0;
+                  n = poll(&pl, 1, 0)"
+. auto/feature
+    
+if [ $ngx_found = no ]; then
+    EVENT_POLL=NONE
+fi
+    
+
+ngx_feature="/dev/poll"
+ngx_feature_name="NGX_HAVE_DEVPOLL"
+ngx_feature_run=no
+ngx_feature_incs="#include <sys/devpoll.h>"
+ngx_feature_libs=
+ngx_feature_test="int  n, dp; struct dvpoll  dvp;
+                  dp = 0;
+                  dvp.dp_fds = NULL;
+                  dvp.dp_nfds = 0;
+                  dvp.dp_timeout = 0;
+                  n = ioctl(dp, DP_POLL, &dvp)"
+. auto/feature
+
+if [ $ngx_found = yes ]; then
+    CORE_SRCS="$CORE_SRCS $DEVPOLL_SRCS"
+    EVENT_MODULES="$EVENT_MODULES $DEVPOLL_MODULE"
+    EVENT_FOUND=YES
+fi
+
+
+if test -z "$NGX_KQUEUE_CHECKED"; then
+    ngx_feature="kqueue"
+    ngx_feature_name="NGX_HAVE_KQUEUE"
+    ngx_feature_run=no
+    ngx_feature_incs="#include <sys/event.h>"
+    ngx_feature_libs=
+    ngx_feature_test="int kq; kq = kqueue()"
+    . auto/feature
+
+    if [ $ngx_found = yes ]; then
+
+        have=NGX_HAVE_CLEAR_EVENT . auto/have
+        EVENT_MODULES="$EVENT_MODULES $KQUEUE_MODULE"
+        CORE_SRCS="$CORE_SRCS $KQUEUE_SRCS"
+        EVENT_FOUND=YES
+
+        ngx_feature="kqueue's NOTE_LOWAT"
+        ngx_feature_name="NGX_HAVE_LOWAT_EVENT"
+        ngx_feature_run=no
+        ngx_feature_incs="#include <sys/event.h>"
+        ngx_feature_libs=
+        ngx_feature_test="struct kevent  kev;
+                          kev.fflags = NOTE_LOWAT;"
+        . auto/feature
+    fi
+fi
+
+if [ "$NGX_SYSTEM" = "NetBSD" ]; then
+
+    # NetBSD 2.0 incompatibly defines kevent.udata as "intptr_t"
+
+    cat << END >> $NGX_AUTO_CONFIG_H
+
+#define NGX_KQUEUE_UDATA_T
+
+END
+
+else
+    cat << END >> $NGX_AUTO_CONFIG_H
+
+#define NGX_KQUEUE_UDATA_T  (void *)
+
+END
+
+fi
+
+
+ngx_feature="crypt()"
+ngx_feature_name=
+ngx_feature_run=no
+ngx_feature_incs=
+ngx_feature_libs=
+ngx_feature_test="crypt(\"test\", \"salt\");"
+. auto/feature
+
+
+if [ $ngx_found = no ]; then
+
+    ngx_feature="crypt() in libcrypt"
+    ngx_feature_libs=-lcrypt
+    . auto/feature
+
+    if [ $ngx_found = yes ]; then
+        CRYPT_LIB="-lcrypt"
+    fi
+fi