new file mode 100644
--- /dev/null
+++ b/src/os/unix/ngx_shared.c
@@ -0,0 +1,96 @@
+
+/*
+ * Copyright (C) Igor Sysoev
+ */
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+
+
+#if (HAVE_MAP_ANON)
+
+void *ngx_create_shared_memory(size_t size, ngx_log_t *log)
+{
+    void  *p;
+
+    p = mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_ANON|MAP_SHARED, -1, 0);
+
+    if (p == MAP_FAILED) {
+        ngx_log_error(NGX_LOG_ALERT, log, ngx_errno,
+                      "mmap(MAP_ANON|MAP_SHARED, " SIZE_T_FMT ") failed",
+                      size);
+        return NULL;
+    }
+
+    return p;
+}
+
+#elif (HAVE_MAP_DEVZERO)
+
+void *ngx_create_shared_memory(size_t size, ngx_log_t *log)
+{
+    void      *p;
+    ngx_fd_t   fd;
+
+    fd = open("/dev/zero", O_RDWR);
+
+    if (fd == -1) {
+        ngx_log_error(NGX_LOG_ALERT, log, ngx_errno,
+                      "open(/dev/zero) failed");
+        return NULL;
+    }
+
+    p = mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
+
+    if (p == MAP_FAILED) {
+        ngx_log_error(NGX_LOG_ALERT, log, ngx_errno,
+                      "mmap(/dev/zero, MAP_SHARED, " SIZE_T_FMT ") failed",
+                      size);
+        p = NULL;
+    }
+
+    if (close(fd) == -1) {
+        ngx_log_error(NGX_LOG_ALERT, log, ngx_errno, "close() failed");
+    }
+
+    return p;
+}
+
+#elif (HAVE_SYSVSHM)
+
+#include <sys/ipc.h>
+#include <sys/shm.h>
+
+
+void *ngx_create_shared_memory(size_t size, ngx_log_t *log)
+{
+    int    id;
+    void  *p;
+
+    id = shmget(IPC_PRIVATE, size, (SHM_R|SHM_W|IPC_CREAT));
+
+    if (id == -1) {
+        ngx_log_error(NGX_LOG_ALERT, log, ngx_errno,
+                      "shmget(" SIZE_T_FMT ") failed", size);
+        return NULL;
+    }
+
+    ngx_log_debug1(NGX_LOG_DEBUG_CORE, log, 0, "shmget id: %d", id);
+
+    p = shmat(id, NULL, 0);
+
+    if (p == (void *) -1) {
+        ngx_log_error(NGX_LOG_ALERT, log, ngx_errno, "shmat() failed");
+        p = NULL;
+    }
+
+    if (shmctl(id, IPC_RMID, NULL) == -1) {
+        ngx_log_error(NGX_LOG_ALERT, log, ngx_errno, "shmctl(IPC_RMID) failed");
+        p = NULL;
+    }
+
+    return p;
+}
+
+#endif