new file mode 100644
--- /dev/null
+++ b/src/os/unix/ngx_socket.c
@@ -0,0 +1,104 @@
+
+/*
+ * Copyright (C) Igor Sysoev
+ */
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+
+
+/*
+ * ioctl(FIONBIO) sets a blocking mode with the single syscall
+ * while fcntl(F_SETFL, ~O_NONBLOCK) needs to learn before
+ * the previous state using fcntl(F_GETFL).
+ *
+ * ioctl() and fcntl() are syscalls on at least FreeBSD 2.x, Linux 2.2
+ * and Solaris 7.
+ *
+ * ioctl() in Linux 2.4 and 2.6 uses BKL, however fcntl(F_SETFL) uses it too.
+ */
+
+
+#if (HAVE_FIONBIO)
+
+int ngx_nonblocking(ngx_socket_t s)
+{
+    u_long  nb;
+
+    nb = 1;
+
+    return ioctl(s, FIONBIO, &nb);
+}
+
+
+int ngx_blocking(ngx_socket_t s)
+{
+    u_long  nb;
+
+    nb = 0;
+
+    return ioctl(s, FIONBIO, &nb);
+}
+
+#endif
+
+
+#ifdef __FreeBSD__
+
+int ngx_tcp_nopush(ngx_socket_t s)
+{
+    int  tcp_nopush;
+
+    tcp_nopush = 1;
+
+    return setsockopt(s, IPPROTO_TCP, TCP_NOPUSH,
+                      (const void *) &tcp_nopush, sizeof(int));
+}
+
+
+int ngx_tcp_push(ngx_socket_t s)
+{
+    int  tcp_nopush;
+
+    tcp_nopush = 0;
+
+    return setsockopt(s, IPPROTO_TCP, TCP_NOPUSH,
+                      (const void *) &tcp_nopush, sizeof(int));
+}
+
+#elif __linux__
+
+int ngx_tcp_nopush(ngx_socket_t s)
+{
+    int  cork;
+
+    cork = 1;
+
+    return setsockopt(s, IPPROTO_TCP, TCP_CORK,
+                      (const void *) &cork, sizeof(int));
+}
+
+int ngx_tcp_push(ngx_socket_t s)
+{
+    int  cork;
+
+    cork = 0;
+
+    return setsockopt(s, IPPROTO_TCP, TCP_CORK,
+                      (const void *) &cork, sizeof(int));
+}
+
+#else
+
+int ngx_tcp_nopush(ngx_socket_t s)
+{
+    return NGX_OK;
+}
+
+int ngx_tcp_push(ngx_socket_t s)
+{
+    return NGX_OK;
+}
+
+#endif