diff --git a/src/core/ngx_buf.h b/src/core/ngx_buf.h
index f2489f1..eb75c3b 100644
--- a/src/core/ngx_buf.h
+++ b/src/core/ngx_buf.h
@@ -142,29 +142,6 @@
         (ngx_buf_in_memory(b) ? (size_t) (b->last - b->pos):                 \
                                 (size_t) (b->file_last - b->file_pos))
 
-#if 0
-
-#define ngx_hunk_in_memory_only(h)                                           \
-         ((h->type & (NGX_HUNK_IN_MEMORY|NGX_HUNK_FILE)) == NGX_HUNK_IN_MEMORY)
-/*
-    ((h->type & (NGX_HUNK_TEMP|NGX_HUNK_MEMORY|NGX_HUNK_MMAP|NGX_HUNK_FILE)) \
-                  == (h->type & (NGX_HUNK_TEMP|NGX_HUNK_MEMORY|NGX_HUNK_MMAP)))
-
-*/
-
-
-
-#define ngx_hunk_special(b)                                                  \
-        (b->type == (b->type & (NGX_HUNK_FLUSH|NGX_HUNK_LAST)))
-
-
-#define ngx_hunk_size(b)                                                     \
-        ((b->type & NGX_HUNK_IN_MEMORY) ? (size_t) (b->last - b->pos):       \
-                                          (size_t) (b->file_last - b->file_pos))
-
-#endif
-
-
 ngx_buf_t *ngx_create_temp_buf(ngx_pool_t *pool, size_t size);
 ngx_chain_t *ngx_create_chain_of_bufs(ngx_pool_t *pool, ngx_bufs_t *bufs);
 
diff --git a/src/core/ngx_connection.h b/src/core/ngx_connection.h
index af85e7d..ecd3c8b 100644
--- a/src/core/ngx_connection.h
+++ b/src/core/ngx_connection.h
@@ -60,6 +60,13 @@
 } ngx_connection_log_error_e;
 
 
+typedef enum {
+     NGX_TCP_NOPUSH_DISABLED = -1,
+     NGX_TCP_NOPUSH_UNSET = 0,
+     NGX_TCP_NOPUSH_SET
+} ngx_connection_tcp_nopush_e;
+
+
 struct ngx_connection_s {
     void             *data;
     ngx_event_t      *read;
diff --git a/src/core/ngx_output_chain.c b/src/core/ngx_output_chain.c
index 0afa697..5ea4fd9 100644
--- a/src/core/ngx_output_chain.c
+++ b/src/core/ngx_output_chain.c
@@ -38,7 +38,7 @@
         }
     }
 
-    /* add the incoming hunk to the chain ctx->in */
+    /* add the incoming buf to the chain ctx->in */
 
     if (in) {
         if (ngx_chain_add_copy(ctx->pool, &ctx->in, in) == NGX_ERROR) {
diff --git a/src/event/modules/ngx_rtsig_module.c b/src/event/modules/ngx_rtsig_module.c
index af5d772..1206245 100644
--- a/src/event/modules/ngx_rtsig_module.c
+++ b/src/event/modules/ngx_rtsig_module.c
@@ -16,10 +16,6 @@
 #define si_fd     __spare__[0]
 
 int sigtimedwait(const sigset_t *set, siginfo_t *info,
-                 const struct timespec *timeout);
-
-
-int sigtimedwait(const sigset_t *set, siginfo_t *info,
                  const struct timespec *timeout)
 {
     return -1;
@@ -105,6 +101,7 @@
 
     sigemptyset(&set);
     sigaddset(&set, rtscf->signo);
+    sigaddset(&set, rtscf->signo + 1);
     sigaddset(&set, SIGIO);
 
     if (sigprocmask(SIG_BLOCK, &set, NULL) == -1) {
@@ -133,12 +130,15 @@
 
 static int ngx_rtsig_add_connection(ngx_connection_t *c)
 {
+    int                signo;
     ngx_rtsig_conf_t  *rtscf;
 
     rtscf = ngx_event_get_conf(ngx_cycle->conf_ctx, ngx_rtsig_module);
 
+    signo = rtscf->signo + c->read->instance;
+
     ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0,
-                   "rtsig add connection: fd:%d signo:%d", c->fd, rtscf->signo);
+                   "rtsig add connection: fd:%d signo:%d", c->fd, signo);
 
     if (fcntl(c->fd, F_SETFL, O_RDWR|O_NONBLOCK|O_ASYNC) == -1) {
         ngx_log_error(NGX_LOG_ALERT, c->log, ngx_errno,
@@ -146,13 +146,13 @@
         return NGX_ERROR;
     }
 
-    if (fcntl(c->fd, F_SETSIG, rtscf->signo) == -1) {
+    if (fcntl(c->fd, F_SETSIG, signo) == -1) {
         ngx_log_error(NGX_LOG_ALERT, c->log, ngx_errno,
                       "fcntl(F_SETSIG) failed");
         return NGX_ERROR;
     }
 
-    if (fcntl(c->fd, F_SETOWN, ngx_getpid()) == -1) {
+    if (fcntl(c->fd, F_SETOWN, ngx_pid) == -1) {
         ngx_log_error(NGX_LOG_ALERT, c->log, ngx_errno,
                       "fcntl(F_SETOWN) failed");
         return NGX_ERROR;
@@ -175,6 +175,9 @@
 
 static int ngx_rtsig_del_connection(ngx_connection_t *c, u_int flags)
 {
+    ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0,
+                   "rtsig del connection: fd:%d", c->fd);
+
     if (!(flags & NGX_CLOSE_EVENT)) {
         if (fcntl(c->fd, F_SETFL, O_RDWR|O_NONBLOCK) == -1) {
             ngx_log_error(NGX_LOG_ALERT, c->log, ngx_errno,
@@ -273,9 +276,9 @@
     ngx_elapsed_msec = tv.tv_sec * 1000 + tv.tv_usec / 1000 - ngx_start_msec;
 
     if (err) {
+        ngx_accept_mutex_unlock();
         ngx_log_error((err == NGX_EINTR) ? NGX_LOG_INFO : NGX_LOG_ALERT,
                       cycle->log, err, "sigtimedwait() failed");
-        ngx_accept_mutex_unlock();
         return NGX_ERROR;
     }
 
@@ -287,17 +290,40 @@
     }
 
     ngx_log_debug3(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
-                   "signo:%d fd:%d band:%X", signo, si.si_fd, si.si_band);
+                   "rtsig signo:%d fd:%d band:%X", signo, si.si_fd, si.si_band);
 
     rtscf = ngx_event_get_conf(ngx_cycle->conf_ctx, ngx_rtsig_module);
 
-    if (signo == rtscf->signo) {
+    if (signo == rtscf->signo || signo == rtscf->signo + 1) {
 
         /* TODO: old_cycles */
 
         c = &ngx_cycle->connections[si.si_fd];
 
-        /* TODO: stale signals */
+        instance = signo - rtscf->signo;
+
+        if (si.si_band & POLLIN) {
+            c->read->returned_instance = instance;
+        }
+
+        if (si.si_band & POLLOUT) {
+            c->write->returned_instance = instance;
+        }
+    
+        if (c->read->instance != instance) {
+
+            /*
+             * the stale event from a file descriptor
+             * that was just closed in this iteration
+             */
+
+            ngx_accept_mutex_unlock();
+
+            ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
+                           "rtsig: stale event " PTR_FMT, c);
+
+            return NGX_OK;
+        }
 
         if (si.si_band & (POLLIN|POLLHUP|POLLERR)) {
             if (c->read->active) {
@@ -307,7 +333,7 @@
                     c->read->event_handler(c->read);
 
                 } else if (c->read->accept) {
-                    if (ngx_accept_disabled > 0) {
+                    if (ngx_accept_disabled <= 0) {
                         c->read->event_handler(c->read);
                     }
 
@@ -371,9 +397,11 @@
 
 
     } else {
+        ngx_accept_mutex_unlock();
+
         ngx_log_error(NGX_LOG_ALERT, cycle->log, 0,
                       "sigtimedwait() returned unexpected signal: %d", signo);
-        ngx_accept_mutex_unlock();
+
         return NGX_ERROR;
     }
 
diff --git a/src/event/ngx_event.c b/src/event/ngx_event.c
index 87747c3..c2c7c89 100644
--- a/src/event/ngx_event.c
+++ b/src/event/ngx_event.c
@@ -372,9 +372,16 @@
         rev->event_handler = &ngx_event_accept;
 
         if (ngx_event_flags & NGX_USE_SIGIO_EVENT) {
-            if (ngx_add_conn(c) == NGX_ERROR) {
-                return NGX_ERROR;
+
+            if (ngx_accept_mutex) {
+                ngx_accept_mutex_held = 0;
+
+            } else {
+                if (ngx_add_conn(c) == NGX_ERROR) {
+                    return NGX_ERROR;
+                }
             }
+
         } else {
             if (ngx_add_event(rev, NGX_READ_EVENT, 0) == NGX_ERROR) {
                 return NGX_ERROR;
diff --git a/src/event/ngx_event_connect.c b/src/event/ngx_event_connect.c
index 0fa0f70..db56f10 100644
--- a/src/event/ngx_event_connect.c
+++ b/src/event/ngx_event_connect.c
@@ -264,6 +264,16 @@
         }
     }
 
+    if (ngx_add_conn) {
+        if (rc == -1) {
+            /* NGX_EINPROGRESS */
+            return NGX_AGAIN;
+        }
+ 
+        ngx_log_debug0(NGX_LOG_DEBUG_EVENT, pc->log, 0, "connected");
+        return NGX_OK;
+    }
+
     if (ngx_event_flags & NGX_USE_AIO_EVENT) {
 
         /* aio, iocp */
@@ -294,8 +304,6 @@
         return NGX_OK;
     }
 
-    /* TODO: epoll */
-
     if (ngx_event_flags & NGX_USE_CLEAR_EVENT) {     /* kqueue */
         event = NGX_CLEAR_EVENT;
 
diff --git a/src/event/ngx_event_pipe.c b/src/event/ngx_event_pipe.c
index 3480986..dac38be 100644
--- a/src/event/ngx_event_pipe.c
+++ b/src/event/ngx_event_pipe.c
@@ -225,7 +225,7 @@
                 /* if there're no bufs to read in then disable a level event */
 
                 ngx_log_debug0(NGX_LOG_DEBUG_EVENT, p->log, 0,
-                               "no pipe hunks to read in");
+                               "no pipe bufs to read in");
     
                 break;
             }
diff --git a/src/http/modules/ngx_http_gzip_filter.c b/src/http/modules/ngx_http_gzip_filter.c
index 4f43f34..eb94975 100644
--- a/src/http/modules/ngx_http_gzip_filter.c
+++ b/src/http/modules/ngx_http_gzip_filter.c
@@ -435,9 +435,9 @@
         }
 
         /*
-         * We preallocate a memory for zlib in one hunk (200K-400K), this
+         * We preallocate a memory for zlib in one buffer (200K-400K), this
          * dicreases a number of malloc() and free() calls and also probably
-         * dicreases a number of syscalls.
+         * dicreases a number of syscalls (sbrk() or so).
          * Besides we free() this memory as soon as the gzipping will complete
          * and do not wait while a whole response will be sent to a client.
          *
diff --git a/src/http/modules/proxy/ngx_http_proxy_upstream.c b/src/http/modules/proxy/ngx_http_proxy_upstream.c
index ed25c8e..643f7fa 100644
--- a/src/http/modules/proxy/ngx_http_proxy_upstream.c
+++ b/src/http/modules/proxy/ngx_http_proxy_upstream.c
@@ -701,7 +701,7 @@
 
     /* rc == NGX_OK */
 
-    if (c->tcp_nopush) {
+    if (c->tcp_nopush == NGX_TCP_NOPUSH_SET) {
         if (ngx_tcp_push(c->fd) == NGX_ERROR) {
             ngx_log_error(NGX_LOG_CRIT, c->log,
                           ngx_socket_errno,
@@ -710,7 +710,7 @@
             return; 
         }
 
-        c->tcp_nopush = 0;
+        c->tcp_nopush = NGX_TCP_NOPUSH_UNSET;
         return;
     }
 
@@ -1138,7 +1138,7 @@
         return;
     }
 
-    /* TODO: preallocate event_pipe hunks, look "Content-Length" */
+    /* TODO: preallocate event_pipe bufs, look "Content-Length" */
 
     rc = ngx_http_send_header(r);
 
diff --git a/src/http/ngx_http_core_module.c b/src/http/ngx_http_core_module.c
index 52e4a27..aeec7d2 100644
--- a/src/http/ngx_http_core_module.c
+++ b/src/http/ngx_http_core_module.c
@@ -567,7 +567,7 @@
 
     if (!clcf->tcp_nopush) {
         /* disable TCP_NOPUSH/TCP_CORK use */
-        r->connection->tcp_nopush = -1;
+        r->connection->tcp_nopush = NGX_TCP_NOPUSH_DISABLED;
     }
 
 
diff --git a/src/http/ngx_http_request.c b/src/http/ngx_http_request.c
index 9487d06..97e1b94 100644
--- a/src/http/ngx_http_request.c
+++ b/src/http/ngx_http_request.c
@@ -92,7 +92,7 @@
     if (rev->ready) {
         /* deferred accept, aio, iocp */
 
-        if (*ngx_accept_mutex) {
+        if (ngx_accept_mutex) {
             if (ngx_mutex_lock(ngx_posted_events_mutex) == NGX_ERROR) {
                 ngx_http_close_connection(c);
                 return;
@@ -562,10 +562,10 @@
 
         /*
          * If it's a pipelined request and a request line is not complete
-         * then we have to copy it to the start of the r->header_in hunk.
+         * then we have to copy it to the start of the r->header_in buf.
          * We have to copy it here only if the large client headers
          * are enabled otherwise a request line had been already copied
-         * to the start of the r->header_in hunk in ngx_http_set_keepalive().
+         * to the start of the r->header_in buf in ngx_http_set_keepalive().
          */
 
         cscf = ngx_http_get_module_srv_conf(r, ngx_http_core_module);
@@ -757,8 +757,10 @@
 
         if (r->header_in->last == r->header_in->end) {
 
-            /* if the large client headers are enabled then
-                we need to compact r->header_in hunk */
+            /*
+             * if the large client headers are enabled then
+             * we need to compact r->header_in buf
+             */
 
             if (cscf->large_client_header) {
                 offset = r->header_name_start - r->header_in->start;
@@ -1315,13 +1317,13 @@
 
     ctx->action = "keepalive";
 
-    if (c->tcp_nopush == 1) {
+    if (c->tcp_nopush == NGX_TCP_NOPUSH_SET) {
         if (ngx_tcp_push(c->fd) == NGX_ERROR) {
             ngx_connection_error(c, ngx_socket_errno, ngx_tcp_push_n " failed");
             ngx_http_close_connection(c);
             return;
         }
-        c->tcp_nopush = 0;
+        c->tcp_nopush = NGX_TCP_NOPUSH_UNSET;
     }
 
     if (rev->ready) {
diff --git a/src/http/ngx_http_request.h b/src/http/ngx_http_request.h
index 77cabb5..cac8aed 100644
--- a/src/http/ngx_http_request.h
+++ b/src/http/ngx_http_request.h
@@ -223,15 +223,6 @@
 
     ngx_http_request_body_t  *request_body;
 
-#if 0
-    ngx_temp_file_t     *temp_file;
-    ngx_chain_t         *request_hunks;
-    ngx_hunk_t          *request_body_hunk;
-    size_t               remaining_body_len;
-    void               (*request_body_handler) (void *data); 
-    void                *data;
-#endif
-
     time_t               lingering_time;
 
     ngx_uint_t           method;
diff --git a/src/http/ngx_http_write_filter.c b/src/http/ngx_http_write_filter.c
index e23649e..48aba43 100644
--- a/src/http/ngx_http_write_filter.c
+++ b/src/http/ngx_http_write_filter.c
@@ -129,8 +129,8 @@
                                         ngx_http_write_filter_module);
 
     /*
-     * avoid the output if there is no last hunk, no flush point,
-     * there are the incoming hunks and the size of all hunks
+     * avoid the output if there is no last buf, no flush point,
+     * there are the incoming bufs and the size of all bufs
      * is smaller than "postpone_output" directive
      */
 
diff --git a/src/os/unix/ngx_files.c b/src/os/unix/ngx_files.c
index 5d551eb..8b906f0 100644
--- a/src/os/unix/ngx_files.c
+++ b/src/os/unix/ngx_files.c
@@ -125,7 +125,7 @@
     ngx_err_t      err;
     ngx_array_t    io;
 
-    /* use pwrite() if there's the only hunk in a chain */
+    /* use pwrite() if there's the only buf in a chain */
 
     if (cl->next == NULL) {
         return ngx_write_file(file, cl->buf->pos,
diff --git a/src/os/unix/ngx_freebsd_sendfile_chain.c b/src/os/unix/ngx_freebsd_sendfile_chain.c
index 694ea22..abc3d19 100644
--- a/src/os/unix/ngx_freebsd_sendfile_chain.c
+++ b/src/os/unix/ngx_freebsd_sendfile_chain.c
@@ -162,7 +162,9 @@
 
         if (file) {
 
-            if (ngx_freebsd_use_tcp_nopush && c->tcp_nopush == 0) {
+            if (ngx_freebsd_use_tcp_nopush
+                && c->tcp_nopush == NGX_TCP_NOPUSH_UNSET)
+            {
 
                 if (ngx_tcp_nopush(c->fd) == NGX_ERROR) {
                     err = ngx_errno;
@@ -180,7 +182,8 @@
                     }
 
                 } else {
-                    c->tcp_nopush = 1;
+                    c->tcp_nopush = NGX_TCP_NOPUSH_SET;
+
                     ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, 0,
                                    "tcp_nopush");
                 }
diff --git a/src/os/unix/ngx_linux_sendfile_chain.c b/src/os/unix/ngx_linux_sendfile_chain.c
index 0c6b9d0..75f51cf 100644
--- a/src/os/unix/ngx_linux_sendfile_chain.c
+++ b/src/os/unix/ngx_linux_sendfile_chain.c
@@ -58,32 +58,32 @@
         /* create the iovec and coalesce the neighbouring bufs */
 
         for (cl = in; cl && header.nelts < IOV_MAX; cl = cl->next) {
-            if (ngx_hunk_special(cl->hunk)) {
+            if (ngx_buf_special(cl->buf)) {
                 continue;
             }
 
-            if (!ngx_hunk_in_memory_only(cl->hunk)) {
+            if (!ngx_buf_in_memory_only(cl->buf)) {
                 break;
             }
 
-            if (prev == cl->hunk->pos) {
-                iov->iov_len += cl->hunk->last - cl->hunk->pos;
+            if (prev == cl->buf->pos) {
+                iov->iov_len += cl->buf->last - cl->buf->pos;
 
             } else {
                 ngx_test_null(iov, ngx_push_array(&header), NGX_CHAIN_ERROR);
-                iov->iov_base = (void *) cl->hunk->pos;
-                iov->iov_len = cl->hunk->last - cl->hunk->pos;
+                iov->iov_base = (void *) cl->buf->pos;
+                iov->iov_len = cl->buf->last - cl->buf->pos;
             }
 
-            prev = cl->hunk->last;
+            prev = cl->buf->last;
         }
 
         /* set TCP_CORK if there is a header before a file */
 
-        if (!c->tcp_nopush == 0
+        if (c->tcp_nopush == NGX_TCP_NOPUSH_UNSET
             && header.nelts != 0
             && cl
-            && cl->hunk->type & NGX_HUNK_FILE)
+            && cl->buf->in_file)
         {
             if (ngx_tcp_nopush(c->fd) == NGX_ERROR) {
                 err = ngx_errno;
@@ -100,32 +100,33 @@
                 }
 
             } else {
-                c->tcp_nopush = 1;
+                c->tcp_nopush = NGX_TCP_NOPUSH_SET;
+
                 ngx_log_debug0(NGX_LOG_DEBUG_EVENT, c->log, 0,
                                "tcp_nopush");
             }
         }
 
-        if (header.nelts == 0 && cl && cl->hunk->type & NGX_HUNK_FILE) {
+        if (header.nelts == 0 && cl && cl->buf->in_file) {
 
-            /* get the file hunk */
+            /* get the file buf */
 
-            file = cl->hunk;
+            file = cl->buf;
             fsize = (size_t) (file->file_last - file->file_pos);
             fprev = file->file_last;
             cl = cl->next; 
 
-            /* coalesce the neighbouring file hunks */
+            /* coalesce the neighbouring file bufs */
 
-            while (cl && (cl->hunk->type & NGX_HUNK_FILE)) {
-                if (file->file->fd != cl->hunk->file->fd
-                    || fprev != cl->hunk->file_pos)
+            while (cl && (cl->buf->in_file)) {
+                if (file->file->fd != cl->buf->file->fd
+                    || fprev != cl->buf->file_pos)
                 {
                     break;
                 }
 
-                fsize += (size_t) (cl->hunk->file_last - cl->hunk->file_pos);
-                fprev = cl->hunk->file_last;
+                fsize += (size_t) (cl->buf->file_last - cl->buf->file_pos);
+                fprev = cl->buf->file_last;
                 cl = cl->next;
             }
         }
@@ -199,7 +200,7 @@
 
         for (cl = in; cl; cl = cl->next) {
 
-            if (ngx_hunk_special(cl->hunk)) {
+            if (ngx_buf_special(cl->buf)) {
                 continue;
             }
 
@@ -207,28 +208,28 @@
                 break;
             }
 
-            size = ngx_hunk_size(cl->hunk);
+            size = ngx_buf_size(cl->buf);
 
             if (sent >= size) {
                 sent -= size;
 
-                if (cl->hunk->type & NGX_HUNK_IN_MEMORY) {
-                    cl->hunk->pos = cl->hunk->last;
+                if (ngx_buf_in_memory(cl->buf)) {
+                    cl->buf->pos = cl->buf->last;
                 }
 
-                if (cl->hunk->type & NGX_HUNK_FILE) {
-                    cl->hunk->file_pos = cl->hunk->file_last;
+                if (cl->buf->in_file) {
+                    cl->buf->file_pos = cl->buf->file_last;
                 }
 
                 continue;
             }
 
-            if (cl->hunk->type & NGX_HUNK_IN_MEMORY) {
-                cl->hunk->pos += sent;
+            if (ngx_buf_in_memory(cl->buf)) {
+                cl->buf->pos += sent;
             }
 
-            if (cl->hunk->type & NGX_HUNK_FILE) {
-                cl->hunk->file_pos += sent;
+            if (cl->buf->in_file) {
+                cl->buf->file_pos += sent;
             }
 
             break;
diff --git a/src/os/unix/ngx_solaris_sendfilev_chain.c b/src/os/unix/ngx_solaris_sendfilev_chain.c
index 964027f..352c162 100644
--- a/src/os/unix/ngx_solaris_sendfilev_chain.c
+++ b/src/os/unix/ngx_solaris_sendfilev_chain.c
@@ -43,42 +43,42 @@
         /* create the sendfilevec and coalesce the neighbouring bufs */
 
         for (cl = in; cl && vec.nelts < IOV_MAX; cl = cl->next) {
-            if (ngx_hunk_special(cl->hunk)) {
+            if (ngx_buf_special(cl->buf)) {
                 continue;
             }
 
-            if (ngx_hunk_in_memory_only(cl->hunk)) {
+            if (ngx_buf_in_memory_only(cl->buf)) {
                 fd = SFV_FD_SELF;
 
-                if (prev == cl->hunk->pos) {
-                    sfv->sfv_len += cl->hunk->last - cl->hunk->pos;
+                if (prev == cl->buf->pos) {
+                    sfv->sfv_len += cl->buf->last - cl->buf->pos;
 
                 } else {
                     ngx_test_null(sfv, ngx_push_array(&vec), NGX_CHAIN_ERROR);
                     sfv->sfv_fd = SFV_FD_SELF;
                     sfv->sfv_flag = 0;
-                    sfv->sfv_off = (off_t) (uintptr_t) cl->hunk->pos;
-                    sfv->sfv_len = cl->hunk->last - cl->hunk->pos;
+                    sfv->sfv_off = (off_t) (uintptr_t) cl->buf->pos;
+                    sfv->sfv_len = cl->buf->last - cl->buf->pos;
                 }
 
-                prev = cl->hunk->last;
+                prev = cl->buf->last;
 
             } else {
                 prev = NULL;
 
-                if (fd == cl->hunk->file->fd && fprev == cl->hunk->file_pos) {
-                    sfv->sfv_len += cl->hunk->file_last - cl->hunk->file_pos;
+                if (fd == cl->buf->file->fd && fprev == cl->buf->file_pos) {
+                    sfv->sfv_len += cl->buf->file_last - cl->buf->file_pos;
 
                 } else {
                     ngx_test_null(sfv, ngx_push_array(&vec), NGX_CHAIN_ERROR);
-                    fd = cl->hunk->file->fd;
+                    fd = cl->buf->file->fd;
                     sfv->sfv_fd = fd;
                     sfv->sfv_flag = 0;
-                    sfv->sfv_off = cl->hunk->file_pos;
-                    sfv->sfv_len = cl->hunk->file_last - cl->hunk->file_pos;
+                    sfv->sfv_off = cl->buf->file_pos;
+                    sfv->sfv_len = cl->buf->file_last - cl->buf->file_pos;
                 }
 
-                fprev = cl->hunk->file_last;
+                fprev = cl->buf->file_last;
             }
         }
 
@@ -117,7 +117,7 @@
 
         for (cl = in; cl; cl = cl->next) {
 
-            if (ngx_hunk_special(cl->hunk)) {
+            if (ngx_buf_special(cl->buf)) {
                 continue; 
             }
 
@@ -125,28 +125,28 @@
                 break;
             }
 
-            size = ngx_hunk_size(cl->hunk);
+            size = ngx_buf_size(cl->buf);
 
             if (sent >= size) {
                 sent -= size;
 
-                if (cl->hunk->type & NGX_HUNK_IN_MEMORY) {
-                    cl->hunk->pos = cl->hunk->last;
+                if (ngx_buf_in_memory(cl->buf)) {
+                    cl->buf->pos = cl->buf->last;
                 }
 
-                if (cl->hunk->type & NGX_HUNK_FILE) {
-                    cl->hunk->file_pos = cl->hunk->file_last;
+                if (cl->buf->in_file) {
+                    cl->buf->file_pos = cl->buf->file_last;
                 }
 
                 continue;
             }
 
-            if (cl->hunk->type & NGX_HUNK_IN_MEMORY) {
-                cl->hunk->pos += sent;
+            if (ngx_buf_in_memory(cl->buf)) {
+                cl->buf->pos += sent;
             }
 
-            if (cl->hunk->type & NGX_HUNK_FILE) {
-                cl->hunk->file_pos += sent;
+            if (cl->buf->in_file) {
+                cl->buf->file_pos += sent;
             }
 
             break;
diff --git a/src/os/win32/ngx_files.c b/src/os/win32/ngx_files.c
index 2185dcf..6ed4ff0 100644
--- a/src/os/win32/ngx_files.c
+++ b/src/os/win32/ngx_files.c
@@ -143,7 +143,7 @@
         prev = buf;
         size = 0;
 
-        /* coalesce the neighbouring hunks */
+        /* coalesce the neighbouring bufs */
 
         while (cl && prev == cl->buf->pos) {
             size += cl->buf->last - cl->buf->pos;
diff --git a/src/os/win32/ngx_wsasend_chain.c b/src/os/win32/ngx_wsasend_chain.c
index 46e03da..4ada9ea 100644
--- a/src/os/win32/ngx_wsasend_chain.c
+++ b/src/os/win32/ngx_wsasend_chain.c
@@ -241,180 +241,3 @@
 
     return cl;
 }
-
-
-#if 0
-
-ngx_chain_t *ngx_wsasend_chain(ngx_connection_t *c, ngx_chain_t *in)
-{
-    int               rc;
-    char             *prev;
-    size_t            size, sent;
-    LPWSABUF          wsabuf;
-    ngx_err_t         err;
-    ngx_event_t      *wev;
-    ngx_array_t       wsabufs;
-    ngx_chain_t      *ce;
-    LPWSAOVERLAPPED   ovlp;
-
-#if 0
-
-iocp:
-    if ready
-       get result
-       update chain
-       return if done;
-    wsasend
-
-non-block
-    for ( ;; ) {
-       wsasend
-       if no again
-          update chain
-          return if done;
-    }
-
-
-    for ( ;; ) {
-
-        make buffers and limit data for both ovlp and nonblocked,
-                     configured in events module
-
-        if (iocp && ready) {
-            get result
-
-        } else {
-            if (file)
-                transmitfile
-            else
-                wsasend
-
-            if (iocp)
-                return chain
-            return chain if again
-            here is result
-        }
-
-        if (result)
-            update chain;
-            return chain if done
-        }
-    }
-
-
-#endif
-
-    wev = c->write;
-
-    if (((ngx_event_flags & NGX_USE_AIO_EVENT) && !wev->ready)
-        || ((ngx_event_flags & NGX_USE_AIO_EVENT) == 0))
-    {
-        /*
-         * WSABUFs must be 4-byte aligned otherwise
-         * WSASend() will return undocumented WSAEINVAL error.
-         */
-
-        ngx_init_array(wsabufs, c->pool, 10, sizeof(WSABUF), NGX_CHAIN_ERROR);
-
-        prev = NULL;
-        wsabuf = NULL;
-
-        /* create the WSABUF and coalesce the neighbouring chain entries */
-        for (ce = in; ce; ce = ce->next) {
-
-            if (prev == ce->hunk->pos) {
-                wsabuf->len += ce->hunk->last - ce->hunk->pos;
-                prev = ce->hunk->last;
-
-            } else {
-                ngx_test_null(wsabuf, ngx_push_array(&wsabufs),
-                              NGX_CHAIN_ERROR);
-                wsabuf->buf = ce->hunk->pos;
-                wsabuf->len = ce->hunk->last - ce->hunk->pos;
-                prev = ce->hunk->last;
-            }
-        }
-
-        if (ngx_event_flags & NGX_USE_AIO_EVENT) {
-            ovlp = (LPWSAOVERLAPPED) &c->write->ovlp;
-            ngx_memzero(ovlp, sizeof(WSAOVERLAPPED));
-
-        } else {
-            ovlp = NULL;
-        }
-
-        rc = WSASend(c->fd, wsabufs.elts, wsabufs.nelts, &sent, 0, ovlp, NULL);
-
-        if (rc == -1) {
-            err = ngx_errno;
-            if (err == WSA_IO_PENDING) {
-                sent = 0;
-
-            } else if (err == WSAEWOULDBLOCK) {
-                sent = 0;
-                ngx_log_error(NGX_LOG_INFO, c->log, err, "WSASend() EAGAIN");
-
-            } else {
-                ngx_log_error(NGX_LOG_CRIT, c->log, err, "WSASend() failed");
-                return NGX_CHAIN_ERROR;
-            }
-
-        } else {
-
-            if (ngx_event_flags & NGX_USE_IOCP_EVENT) {
-
-                /*
-                 * If a socket was bound with I/O completion port then
-                 * GetQueuedCompletionStatus() would anyway return its status
-                 * despite that WSASend() was already completed.
-                 */
-
-                sent = 0;
-            }
-        }
-
-    } else {
-        if (ngx_event_flags & NGX_USE_IOCP_EVENT) {
-            wev->ready = 0;
-
-            /* the overlapped WSASend() completed */
-
-            if (wev->ovlp.error) {
-                ngx_log_error(NGX_LOG_ERR, c->log, wev->ovlp.error,
-                              "WSASend() failed");
-                return NGX_CHAIN_ERROR;
-            }
-
-            sent = wev->available;
-        }
-    }
-
-    ngx_log_debug(c->log, "WSASend(): %d" _ sent);
-
-    c->sent += sent;
-
-    for (ce = in; ce && sent > 0; ce = ce->next) {
-
-        size = ce->hunk->last - ce->hunk->pos;
-
-        if (sent >= size) {
-            sent -= size;
-
-            if (ce->hunk->type & NGX_HUNK_IN_MEMORY) {
-                ce->hunk->pos = ce->hunk->last;
-            }
-
-            continue;
-        }
-
-        if (ce->hunk->type & NGX_HUNK_IN_MEMORY) {
-            ce->hunk->pos += sent;
-        }
-
-        break;
-    }
-
-    return ce;
-}
-
-#endif