new file mode 100644
--- /dev/null
+++ b/src/os/unix/ngx_process.c
@@ -0,0 +1,283 @@
+
+/*
+ * Copyright (C) Igor Sysoev
+ */
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+#include <ngx_event.h>
+#include <ngx_channel.h>
+
+
+static void ngx_execute_proc(ngx_cycle_t *cycle, void *data);
+
+ngx_int_t      ngx_process_slot;
+ngx_socket_t   ngx_channel;
+ngx_int_t      ngx_last_process;
+ngx_process_t  ngx_processes[NGX_MAX_PROCESSES];
+
+
+ngx_pid_t ngx_spawn_process(ngx_cycle_t *cycle,
+                            ngx_spawn_proc_pt proc, void *data,
+                            char *name, ngx_int_t respawn)
+{
+    u_long     on;
+    ngx_pid_t  pid;
+    ngx_int_t  s;
+
+    if (respawn >= 0) {
+        s = respawn;
+
+    } else {
+        for (s = 0; s < ngx_last_process; s++) {
+            if (ngx_processes[s].pid == -1) {
+                break;
+            }
+        }
+
+        if (s == NGX_MAX_PROCESSES) {
+            ngx_log_error(NGX_LOG_ALERT, cycle->log, 0,
+                          "no more than %d processes can be spawned",
+                          NGX_MAX_PROCESSES);
+            return NGX_ERROR;
+        }
+    }
+
+
+    if (respawn != NGX_PROCESS_DETACHED) {
+
+        /* Solaris 9 still has no AF_LOCAL */
+
+        if (socketpair(AF_UNIX, SOCK_STREAM, 0, ngx_processes[s].channel) == -1)
+        {
+            ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
+                          "socketpair() failed while spawning \"%s\"", name);
+            return NGX_ERROR;
+        }
+
+        ngx_log_debug2(NGX_LOG_DEBUG_CORE, cycle->log, 0,
+                       "channel %d:%d",
+                       ngx_processes[s].channel[0],
+                       ngx_processes[s].channel[1]);
+
+        if (ngx_nonblocking(ngx_processes[s].channel[0]) == -1) {
+            ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
+                          ngx_nonblocking_n " failed while spawning \"%s\"",
+                          name);
+            ngx_close_channel(ngx_processes[s].channel, cycle->log);
+            return NGX_ERROR;
+        }
+
+        if (ngx_nonblocking(ngx_processes[s].channel[1]) == -1) {
+            ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
+                          ngx_nonblocking_n " failed while spawning \"%s\"",
+                          name);
+            ngx_close_channel(ngx_processes[s].channel, cycle->log);
+            return NGX_ERROR;
+        }
+
+        on = 1;
+        if (ioctl(ngx_processes[s].channel[0], FIOASYNC, &on) == -1) {
+            ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
+                          "ioctl(FIOASYNC) failed while spawning \"%s\"", name);
+            ngx_close_channel(ngx_processes[s].channel, cycle->log);
+            return NGX_ERROR;
+        }
+
+        if (fcntl(ngx_processes[s].channel[0], F_SETOWN, ngx_pid) == -1) {
+            ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
+                          "fcntl(F_SETOWN) failed while spawning \"%s\"", name);
+            ngx_close_channel(ngx_processes[s].channel, cycle->log);
+            return NGX_ERROR;
+        }
+
+        if (fcntl(ngx_processes[s].channel[0], F_SETFD, FD_CLOEXEC) == -1) {
+            ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
+                          "fcntl(FD_CLOEXEC) failed while spawning \"%s\"",
+                           name);
+            ngx_close_channel(ngx_processes[s].channel, cycle->log);
+            return NGX_ERROR;
+        }
+
+        if (fcntl(ngx_processes[s].channel[1], F_SETFD, FD_CLOEXEC) == -1) {
+            ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
+                          "fcntl(FD_CLOEXEC) failed while spawning \"%s\"",
+                           name);
+            ngx_close_channel(ngx_processes[s].channel, cycle->log);
+            return NGX_ERROR;
+        }
+
+        ngx_channel = ngx_processes[s].channel[1];
+
+    } else {
+        ngx_processes[s].channel[0] = -1;
+        ngx_processes[s].channel[1] = -1;
+    }
+
+    ngx_process_slot = s;
+
+
+    pid = fork();
+
+    switch (pid) {
+
+    case -1:
+        ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
+                      "fork() failed while spawning \"%s\"", name);
+        ngx_close_channel(ngx_processes[s].channel, cycle->log);
+        return NGX_ERROR;
+
+    case 0:
+        ngx_pid = ngx_getpid();
+        proc(cycle, data);
+        break;
+
+    default:
+        break;
+    }
+
+    ngx_log_debug2(NGX_LOG_DEBUG_CORE, cycle->log, 0,
+                   "spawn %s: " PID_T_FMT, name, pid);
+
+    ngx_processes[s].pid = pid;
+    ngx_processes[s].exited = 0;
+
+    if (respawn >= 0) {
+        return pid;
+    }
+
+    ngx_processes[s].proc = proc;
+    ngx_processes[s].data = data;
+    ngx_processes[s].name = name;
+    ngx_processes[s].exiting = 0;
+
+    switch (respawn) {
+
+    case NGX_PROCESS_RESPAWN:
+        ngx_processes[s].respawn = 1;
+        ngx_processes[s].just_respawn = 0;
+        ngx_processes[s].detached = 0;
+        break;
+
+    case NGX_PROCESS_JUST_RESPAWN:
+        ngx_processes[s].respawn = 1;
+        ngx_processes[s].just_respawn = 1;
+        ngx_processes[s].detached = 0;
+        break;
+
+    case NGX_PROCESS_DETACHED:
+        ngx_processes[s].respawn = 0;
+        ngx_processes[s].just_respawn = 0;
+        ngx_processes[s].detached = 1;
+        break;
+    }
+
+    if (s == ngx_last_process) {
+        ngx_last_process++;
+    }
+
+    return pid;
+}
+
+
+ngx_pid_t ngx_execute(ngx_cycle_t *cycle, ngx_exec_ctx_t *ctx)
+{
+    return ngx_spawn_process(cycle, ngx_execute_proc, ctx, ctx->name,
+                             NGX_PROCESS_DETACHED);
+}
+
+
+static void ngx_execute_proc(ngx_cycle_t *cycle, void *data)
+{
+    ngx_exec_ctx_t  *ctx = data;
+
+    if (execve(ctx->path, ctx->argv, ctx->envp) == -1) {
+        ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
+                      "execve() failed while executing %s \"%s\"",
+                      ctx->name, ctx->path);
+    }
+
+    exit(1);
+}
+
+
+void ngx_process_get_status()
+{
+    int              status;
+    char            *process;
+    ngx_pid_t        pid;
+    ngx_err_t        err;
+    ngx_int_t        i;
+    ngx_uint_t       one;
+    struct timeval   tv;
+    one = 0;
+
+    for ( ;; ) {
+        pid = waitpid(-1, &status, WNOHANG);
+
+        if (pid == 0) {
+            return;
+        }
+
+        if (pid == -1) {
+            err = ngx_errno;
+
+            if (err == NGX_EINTR) {
+                continue;
+            }
+
+            if (err == NGX_ECHILD && one) {
+                return;
+            }
+
+            ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, errno,
+                          "waitpid() failed");
+            return;
+        }
+
+
+        if (ngx_accept_mutex_ptr) {
+
+            /*
+             * unlock the accept mutex if the abnormally exited process
+             * held it
+             */
+
+            ngx_atomic_cmp_set(ngx_accept_mutex_ptr, pid, 0);
+        }
+
+
+        one = 1;
+        process = "unknown process";
+
+        for (i = 0; i < ngx_last_process; i++) {
+            if (ngx_processes[i].pid == pid) {
+                ngx_processes[i].status = status;
+                ngx_processes[i].exited = 1;
+                process = ngx_processes[i].name;
+                break;
+            }
+        }
+
+        if (WTERMSIG(status)) {
+            ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, 0,
+                          "%s " PID_T_FMT " exited on signal %d%s",
+                          process, pid, WTERMSIG(status),
+                          WCOREDUMP(status) ? " (core dumped)" : "");
+
+        } else {
+            ngx_log_error(NGX_LOG_INFO, ngx_cycle->log, 0,
+                          "%s " PID_T_FMT " exited with code %d",
+                          process, pid, WEXITSTATUS(status));
+        }
+
+        if (WEXITSTATUS(status) == 2 && ngx_processes[i].respawn) {
+            ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, 0,
+                          "%s " PID_T_FMT
+                          " exited with fatal code %d and could not respawn",
+                          process, pid, WEXITSTATUS(status));
+            ngx_processes[i].respawn = 0;
+        }
+    }
+}