diff --git a/src/mdbx.c b/src/mdbx.c
index 7cc2c97c..a1059ea2 100644
--- a/src/mdbx.c
+++ b/src/mdbx.c
@@ -11281,6 +11281,7 @@ static THREAD_RESULT __cold THREAD_CALL mdbx_env_copythr(void *arg) {
   uint8_t *ptr;
   int toggle = 0;
   int rc;
+  size_t offset = pgno2bytes(my->mc_env, NUM_METAS);
 
 #if defined(F_SETNOSIGPIPE)
   /* OS X delivers SIGPIPE to the whole process, not the thread that caused it.
@@ -11309,7 +11310,7 @@ static THREAD_RESULT __cold THREAD_CALL mdbx_env_copythr(void *arg) {
     ptr = my->mc_wbuf[toggle];
   again:
     if (wsize > 0 && !my->mc_error) {
-      rc = mdbx_write(my->mc_fd, ptr, wsize);
+      rc = mdbx_pwrite(my->mc_fd, ptr, wsize, offset);
       if (rc != MDBX_SUCCESS) {
 #if defined(SIGPIPE) && !defined(_WIN32) && !defined(_WIN64)
         if (rc == EPIPE) {
@@ -11320,7 +11321,9 @@ static THREAD_RESULT __cold THREAD_CALL mdbx_env_copythr(void *arg) {
         }
 #endif
         my->mc_error = rc;
+        break;
       }
+      offset += wsize;
     }
 
     /* If there's an overflow page tail, write it too */
@@ -11708,7 +11711,7 @@ int __cold mdbx_env_copy2fd(MDBX_env *env, mdbx_filehandle_t fd,
   /* Firstly write a stub to meta-pages.
    * Now we sure to incomplete copy will not be used. */
   memset(buffer, -1, pgno2bytes(env, NUM_METAS));
-  rc = mdbx_write(fd, buffer, pgno2bytes(env, NUM_METAS));
+  rc = mdbx_pwrite(fd, buffer, pgno2bytes(env, NUM_METAS), 0);
   if (likely(rc == MDBX_SUCCESS)) {
     memset(buffer, 0, pgno2bytes(env, NUM_METAS));
     rc = (flags & MDBX_CP_COMPACT)
diff --git a/src/osal.c b/src/osal.c
index a8f88383..2ee74441 100644
--- a/src/osal.c
+++ b/src/osal.c
@@ -1,4 +1,4 @@
-/* https://en.wikipedia.org/wiki/Operating_system_abstraction_layer */
+/* https://en.wikipedia.org/wiki/Operating_system_abstraction_layer */
 
 /*
  * Copyright 2015-2019 Leonid Yuriev <leo@yuriev.ru>
@@ -569,21 +569,21 @@ int mdbx_pread(mdbx_filehandle_t fd, void *buf, size_t bytes, uint64_t offset) {
 
 int mdbx_pwrite(mdbx_filehandle_t fd, const void *buf, size_t bytes,
                 uint64_t offset) {
-#if defined(_WIN32) || defined(_WIN64)
-  if (bytes > MAX_WRITE)
-    return ERROR_INVALID_PARAMETER;
-
-  OVERLAPPED ov;
-  ov.hEvent = 0;
-  ov.Offset = (DWORD)offset;
-  ov.OffsetHigh = HIGH_DWORD(offset);
-
-  DWORD written;
-  if (likely(WriteFile(fd, buf, (DWORD)bytes, &written, &ov)))
-    return (bytes == written) ? MDBX_SUCCESS : MDBX_EIO /* ERROR_WRITE_FAULT */;
-  return GetLastError();
-#else
   while (true) {
+#if defined(_WIN32) || defined(_WIN64)
+    OVERLAPPED ov;
+    ov.hEvent = 0;
+    ov.Offset = (DWORD)offset;
+    ov.OffsetHigh = HIGH_DWORD(offset);
+
+    DWORD written;
+    if (unlikely(!WriteFile(fd, buf,
+                            (bytes <= MAX_WRITE) ? (DWORD)bytes : MAX_WRITE,
+                            &written, &ov)))
+      return GetLastError();
+    if (likely(bytes == written))
+      return MDBX_SUCCESS;
+#else
     STATIC_ASSERT_MSG(sizeof(off_t) >= sizeof(size_t),
                       "libmdbx requires 64-bit file I/O on 64-bit systems");
     const intptr_t written =
@@ -594,15 +594,13 @@ int mdbx_pwrite(mdbx_filehandle_t fd, const void *buf, size_t bytes,
       const int rc = errno;
       if (rc != EINTR)
         return rc;
-    } else if (written > 0) {
-      bytes -= written;
-      offset += written;
-      buf = (char *)buf + written;
-    } else {
-      return -1;
+      continue;
     }
-  }
 #endif
+    bytes -= written;
+    offset += written;
+    buf = (char *)buf + written;
+  }
 }
 
 int mdbx_pwritev(mdbx_filehandle_t fd, struct iovec *iov, int iovcnt,
@@ -633,52 +631,6 @@ int mdbx_pwritev(mdbx_filehandle_t fd, struct iovec *iov, int iovcnt,
 #endif
 }
 
-int mdbx_write(mdbx_filehandle_t fd, const void *buf, size_t bytes) {
-#ifdef SIGPIPE
-  sigset_t set, old;
-  sigemptyset(&set);
-  sigaddset(&set, SIGPIPE);
-  int rc = pthread_sigmask(SIG_BLOCK, &set, &old);
-  if (rc != 0)
-    return rc;
-#endif
-
-  const char *ptr = buf;
-  for (;;) {
-    size_t chunk = (MAX_WRITE < bytes) ? MAX_WRITE : bytes;
-#if defined(_WIN32) || defined(_WIN64)
-    DWORD written;
-    if (unlikely(!WriteFile(fd, ptr, (DWORD)chunk, &written, NULL)))
-      return GetLastError();
-#else
-    intptr_t written = write(fd, ptr, chunk);
-    if (written < 0) {
-      int rc = errno;
-#ifdef SIGPIPE
-      if (rc == EPIPE) {
-        /* Collect the pending SIGPIPE, otherwise at least OS X
-         * gives it to the process on thread-exit (ITS#8504). */
-        int tmp;
-        sigwait(&set, &tmp);
-        written = 0;
-        continue;
-      }
-      pthread_sigmask(SIG_SETMASK, &old, NULL);
-#endif
-      return rc;
-    }
-#endif
-    if (likely(bytes == (size_t)written)) {
-#ifdef SIGPIPE
-      pthread_sigmask(SIG_SETMASK, &old, NULL);
-#endif
-      return MDBX_SUCCESS;
-    }
-    ptr += written;
-    bytes -= written;
-  }
-}
-
 int mdbx_filesync(mdbx_filehandle_t fd, bool filesize_changed) {
 #if defined(_WIN32) || defined(_WIN64)
   (void)filesize_changed;
diff --git a/src/osal.h b/src/osal.h
index 0208a522..c3e72e83 100644
--- a/src/osal.h
+++ b/src/osal.h
@@ -1,4 +1,4 @@
-/* https://en.wikipedia.org/wiki/Operating_system_abstraction_layer */
+/* https://en.wikipedia.org/wiki/Operating_system_abstraction_layer */
 
 /*
  * Copyright 2015-2019 Leonid Yuriev <leo@yuriev.ru>
@@ -494,7 +494,6 @@ int mdbx_pwritev(mdbx_filehandle_t fd, struct iovec *iov, int iovcnt,
 int mdbx_pread(mdbx_filehandle_t fd, void *buf, size_t count, uint64_t offset);
 int mdbx_pwrite(mdbx_filehandle_t fd, const void *buf, size_t count,
                 uint64_t offset);
-int mdbx_write(mdbx_filehandle_t fd, const void *buf, size_t count);
 
 int mdbx_thread_create(mdbx_thread_t *thread,
                        THREAD_RESULT(THREAD_CALL *start_routine)(void *),