new file mode 100644
--- /dev/null
+++ b/src/os/unix/ngx_posix_init.c
@@ -0,0 +1,299 @@
+
+/*
+ * Copyright (C) Igor Sysoev
+ */
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+
+
+ngx_int_t  ngx_ncpu;
+ngx_int_t  ngx_max_sockets;
+ngx_int_t  ngx_inherited_nonblocking;
+
+
+struct rlimit  rlmt;
+
+
+#if (NGX_POSIX_IO)
+
+ngx_os_io_t ngx_os_io = {
+    ngx_unix_recv,
+    ngx_readv_chain,
+    NULL,
+    ngx_writev_chain,
+    0
+};
+
+
+int ngx_os_init(ngx_log_t *log)
+{
+    return ngx_posix_init(log);
+}
+
+
+#endif
+
+
+void ngx_signal_handler(int signo);
+
+
+typedef struct {
+     int     signo;
+     char   *signame;
+     void  (*handler)(int signo);
+} ngx_signal_t;
+
+
+ngx_signal_t  signals[] = {
+    { ngx_signal_value(NGX_RECONFIGURE_SIGNAL),
+      "SIG" ngx_value(NGX_RECONFIGURE_SIGNAL),
+      ngx_signal_handler },
+
+    { ngx_signal_value(NGX_REOPEN_SIGNAL),
+      "SIG" ngx_value(NGX_REOPEN_SIGNAL),
+      ngx_signal_handler },
+
+    { ngx_signal_value(NGX_NOACCEPT_SIGNAL),
+      "SIG" ngx_value(NGX_NOACCEPT_SIGNAL),
+      ngx_signal_handler },
+
+    { ngx_signal_value(NGX_TERMINATE_SIGNAL),
+      "SIG" ngx_value(NGX_TERMINATE_SIGNAL),
+      ngx_signal_handler },
+
+    { ngx_signal_value(NGX_SHUTDOWN_SIGNAL),
+      "SIG" ngx_value(NGX_SHUTDOWN_SIGNAL),
+      ngx_signal_handler },
+
+    { ngx_signal_value(NGX_CHANGEBIN_SIGNAL),
+      "SIG" ngx_value(NGX_CHANGEBIN_SIGNAL),
+      ngx_signal_handler },
+
+    { SIGALRM, "SIGALRM", ngx_signal_handler },
+
+    { SIGINT, "SIGINT", ngx_signal_handler },
+
+    { SIGIO, "SIGIO", ngx_signal_handler },
+
+    { SIGCHLD, "SIGCHLD", ngx_signal_handler },
+
+    { SIGPIPE, "SIGPIPE, SIG_IGN", SIG_IGN },
+
+    { 0, NULL, NULL }
+};
+
+
+ngx_int_t ngx_posix_init(ngx_log_t *log)
+{
+    ngx_signal_t      *sig;
+    struct sigaction   sa;
+
+    ngx_pagesize = getpagesize();
+
+    if (ngx_ncpu == 0) {
+        ngx_ncpu = 1;
+    }
+
+    for (sig = signals; sig->signo != 0; sig++) {
+        ngx_memzero(&sa, sizeof(struct sigaction));
+        sa.sa_handler = sig->handler;
+        sigemptyset(&sa.sa_mask);
+        if (sigaction(sig->signo, &sa, NULL) == -1) {
+            ngx_log_error(NGX_LOG_EMERG, log, ngx_errno,
+                          "sigaction(%s) failed", sig->signame);
+            return NGX_ERROR;
+        }
+    }
+
+    if (getrlimit(RLIMIT_NOFILE, &rlmt) == -1) {
+        ngx_log_error(NGX_LOG_ALERT, log, errno,
+                      "getrlimit(RLIMIT_NOFILE) failed)");
+        return NGX_ERROR;
+    }
+
+    ngx_max_sockets = rlmt.rlim_cur;
+
+#if (HAVE_INHERITED_NONBLOCK)
+    ngx_inherited_nonblocking = 1;
+#else
+    ngx_inherited_nonblocking = 0;
+#endif
+
+    return NGX_OK;
+}
+
+
+void ngx_posix_status(ngx_log_t *log)
+{
+    ngx_log_error(NGX_LOG_INFO, log, 0,
+                  "getrlimit(RLIMIT_NOFILE): " RLIM_T_FMT ":" RLIM_T_FMT,
+                  rlmt.rlim_cur, rlmt.rlim_max);
+}
+
+
+void ngx_signal_handler(int signo)
+{
+    char            *action;
+    struct timeval   tv;
+    ngx_int_t        ignore;
+    ngx_err_t        err;
+    ngx_signal_t    *sig;
+
+    ignore = 0;
+
+    err = ngx_errno;
+
+    for (sig = signals; sig->signo != 0; sig++) {
+        if (sig->signo == signo) {
+            break;
+        }
+    }
+
+    ngx_gettimeofday(&tv);
+    ngx_time_update(tv.tv_sec);
+
+    action = "";
+
+    switch (ngx_process) {
+
+    case NGX_PROCESS_MASTER:
+    case NGX_PROCESS_SINGLE:
+        switch (signo) {
+
+        case ngx_signal_value(NGX_SHUTDOWN_SIGNAL):
+            ngx_quit = 1;
+            action = ", shutting down";
+            break;
+
+        case ngx_signal_value(NGX_TERMINATE_SIGNAL):
+        case SIGINT:
+            ngx_terminate = 1;
+            action = ", exiting";
+            break;
+
+        case ngx_signal_value(NGX_NOACCEPT_SIGNAL):
+            ngx_noaccept = 1;
+            action = ", stop the accepting connections";
+            break;
+
+        case ngx_signal_value(NGX_RECONFIGURE_SIGNAL):
+            ngx_reconfigure = 1;
+            action = ", reconfiguring";
+            break;
+
+        case ngx_signal_value(NGX_REOPEN_SIGNAL):
+            ngx_reopen = 1;
+            action = ", reopen logs";
+            break;
+
+        case ngx_signal_value(NGX_CHANGEBIN_SIGNAL):
+            if (getppid() > 1 || ngx_new_binary > 0) {
+
+                /*
+                 * Ignore the signal in the new binary if its parent is
+                 * not the init process, i.e. the old binary's process
+                 * is still running.  Or ingore the signal in the old binary's
+                 * process if the new binary's process is already running.
+                 */
+
+                action = ", ignoring";
+                ignore = 1;
+                break;
+            }
+
+            ngx_change_binary = 1;
+            action = ", changing binary";
+            break;
+
+        case SIGALRM:
+            if (!ngx_terminate) {
+                ngx_timer = 1;
+                action = ", shutting down old worker processes";
+            }
+
+            break;
+
+        case SIGIO:
+            ngx_sigio = 1;
+            break;
+
+        case SIGCHLD:
+            ngx_reap = 1;
+            break;
+        }
+
+        break;
+
+    case NGX_PROCESS_WORKER:
+        switch (signo) {
+
+        case ngx_signal_value(NGX_SHUTDOWN_SIGNAL):
+            ngx_quit = 1;
+            action = ", shutting down";
+            break;
+
+        case ngx_signal_value(NGX_TERMINATE_SIGNAL):
+        case SIGINT:
+            ngx_terminate = 1;
+            action = ", exiting";
+            break;
+
+        case ngx_signal_value(NGX_REOPEN_SIGNAL):
+            ngx_reopen = 1;
+            action = ", reopen logs";
+            break;
+
+        case ngx_signal_value(NGX_RECONFIGURE_SIGNAL):
+        case ngx_signal_value(NGX_NOACCEPT_SIGNAL):
+        case ngx_signal_value(NGX_CHANGEBIN_SIGNAL):
+        case SIGIO:
+            action = ", ignoring";
+            break;
+        }
+
+        break;
+    }
+
+    ngx_log_error(NGX_LOG_INFO, ngx_cycle->log, 0,
+                  "signal %d (%s) received%s", signo, sig->signame, action);
+
+    if (ignore) {
+        ngx_log_error(NGX_LOG_CRIT, ngx_cycle->log, 0,
+                      "the changing binary signal is ignored: "
+                      "you should shutdown or terminate "
+                      "before either old or new binary's process");
+    }
+
+    if (signo == SIGCHLD) {
+        ngx_process_get_status();
+    }
+
+    ngx_set_errno(err);
+}
+
+
+int ngx_posix_post_conf_init(ngx_log_t *log)
+{
+    ngx_fd_t  pp[2];
+
+    if (pipe(pp) == -1) {
+        ngx_log_error(NGX_LOG_EMERG, log, ngx_errno, "pipe() failed");
+        return NGX_ERROR;
+    }
+
+    if (dup2(pp[1], STDERR_FILENO) == -1) {
+        ngx_log_error(NGX_LOG_EMERG, log, errno, "dup2(STDERR) failed");
+        return NGX_ERROR;
+    }
+
+    if (pp[1] > STDERR_FILENO) {
+        if (close(pp[1]) == -1) {
+            ngx_log_error(NGX_LOG_EMERG, log, errno, "close() failed");
+            return NGX_ERROR;
+        }
+    }
+
+    return NGX_OK;
+}