diff --git a/contrib/puff/pufftest.c b/contrib/puff/pufftest.c
index 328cb9f..19230b9 100644
--- a/contrib/puff/pufftest.c
+++ b/contrib/puff/pufftest.c
@@ -16,6 +16,10 @@
    testing, and causes pufftest to fail with not enough output space (-f does
    a write like -w, so -w is not required). */
 
+#if defined(_WIN32) && !defined(_CRT_NONSTDC_NO_DEPRECATE)
+#  define _CRT_NONSTDC_NO_DEPRECATE
+#endif
+
 #include <stdio.h>
 #include <stdlib.h>
 #include "puff.h"
@@ -23,7 +27,7 @@
 #if defined(MSDOS) || defined(OS2) || defined(WIN32) || defined(__CYGWIN__)
 #  include <fcntl.h>
 #  include <io.h>
-#  define SET_BINARY_MODE(file) _setmode(_fileno(file), O_BINARY)
+#  define SET_BINARY_MODE(file) setmode(fileno(file), O_BINARY)
 #else
 #  define SET_BINARY_MODE(file)
 #endif
diff --git a/examples/gznorm.c b/examples/gznorm.c
index 2a1dda8..e8d9b48 100644
--- a/examples/gznorm.c
+++ b/examples/gznorm.c
@@ -10,6 +10,10 @@
 // the data, so it is fast, but no advantage is gained from the history that
 // could be available across member boundaries.
 
+#if defined(_WIN32) && !defined(_CRT_NONSTDC_NO_DEPRECATE)
+#  define _CRT_NONSTDC_NO_DEPRECATE
+#endif
+
 #include <stdio.h>      // fread, fwrite, putc, fflush, ferror, fprintf,
                         // vsnprintf, stdout, stderr, NULL, FILE
 #include <stdlib.h>     // malloc, free
@@ -24,7 +28,7 @@
 #if defined(MSDOS) || defined(OS2) || defined(WIN32) || defined(__CYGWIN__)
 #  include <fcntl.h>
 #  include <io.h>
-#  define SET_BINARY_MODE(file) _setmode(_fileno(file), O_BINARY)
+#  define SET_BINARY_MODE(file) setmode(fileno(file), O_BINARY)
 #else
 #  define SET_BINARY_MODE(file)
 #endif
diff --git a/examples/zpipe.c b/examples/zpipe.c
index 184fce5..51dec47 100644
--- a/examples/zpipe.c
+++ b/examples/zpipe.c
@@ -12,6 +12,10 @@
                      Avoid some compiler warnings for input and output buffers
  */
 
+#if defined(_WIN32) && !defined(_CRT_NONSTDC_NO_DEPRECATE)
+#  define _CRT_NONSTDC_NO_DEPRECATE
+#endif
+
 #include <stdio.h>
 #include <string.h>
 #include <assert.h>
@@ -20,7 +24,7 @@
 #if defined(MSDOS) || defined(OS2) || defined(WIN32) || defined(__CYGWIN__)
 #  include <fcntl.h>
 #  include <io.h>
-#  define SET_BINARY_MODE(file) _setmode(_fileno(file), O_BINARY)
+#  define SET_BINARY_MODE(file) setmode(fileno(file), O_BINARY)
 #else
 #  define SET_BINARY_MODE(file)
 #endif
diff --git a/gzguts.h b/gzguts.h
index bd0a6fe..a6485ab 100644
--- a/gzguts.h
+++ b/gzguts.h
@@ -20,6 +20,9 @@
 #if defined(_WIN32) && !defined(_CRT_SECURE_NO_WARNINGS)
 #  define _CRT_SECURE_NO_WARNINGS
 #endif
+#if defined(_WIN32) && !defined(_CRT_NONSTDC_NO_DEPRECATE)
+#  define _CRT_NONSTDC_NO_DEPRECATE
+#endif
 
 #include <stdio.h>
 #include "zlib.h"
@@ -40,7 +43,6 @@
 
 #if defined(__TURBOC__) || defined(_MSC_VER) || defined(_WIN32)
 #  include <io.h>
-#  include <share.h>
 #  include <sys/stat.h>
 #endif
 
@@ -48,13 +50,6 @@
 #  define WIDECHAR
 #endif
 
-#if defined(_WIN32) || defined(WINAPI_FAMILY)
-#  define open _open
-#  define read _read
-#  define write _write
-#  define close _close
-#endif
-
 #ifdef NO_DEFLATE       /* for compatibility with old definition */
 #  define NO_GZCOMPRESS
 #endif
diff --git a/gzlib.c b/gzlib.c
index 05a9ae5..e485a27 100644
--- a/gzlib.c
+++ b/gzlib.c
@@ -5,15 +5,17 @@
 
 #include "gzguts.h"
 
-#if defined(_WIN32) && !defined(__BORLANDC__)
+#if defined(UNDER_CE)
+#  define LSEEK _wcelseek
+#elif defined(__DJGPP__)
+#  define LSEEK llseek
+#elif defined(_WIN32) && !defined(__BORLANDC__)
 #  define LSEEK _lseeki64
-#else
-#if defined(_LARGEFILE64_SOURCE) && _LFS64_LARGEFILE-0
+#elif defined(_LARGEFILE64_SOURCE) && _LFS64_LARGEFILE-0
 #  define LSEEK lseek64
 #else
 #  define LSEEK lseek
 #endif
-#endif
 
 #if defined UNDER_CE
 
@@ -52,8 +54,7 @@ char ZLIB_INTERNAL *gz_strwinerror(DWORD error) {
             msgbuf[chars] = 0;
         }
 
-        z_size_t len;
-        wcstombs_s(&len, buf, sizeof(buf), msgbuf, chars + 1);
+        wcstombs(buf, msgbuf, chars + 1);       // assumes buf is big enough
         LocalFree(msgbuf);
     }
     else {
@@ -180,10 +181,8 @@ local gzFile gz_open(const void *path, int fd, const char *mode) {
 
     /* save the path name for error messages */
 #ifdef WIDECHAR
-    if (fd == -2) {
-        if (wcstombs_s(&len, NULL, 0, path, 0) != 0)
-            len = 0;
-    }
+    if (fd == -2)
+        len = wcstombs(NULL, path, 0);
     else
 #endif
         len = strlen((const char *)path);
@@ -193,18 +192,21 @@ local gzFile gz_open(const void *path, int fd, const char *mode) {
         return NULL;
     }
 #ifdef WIDECHAR
-    if (fd == -2)
+    if (fd == -2) {
         if (len)
-            wcstombs_s(&len, state->path, len + 1, path, len + 1);
+            wcstombs(state->path, path, len + 1);
         else
             *(state->path) = 0;
+    }
     else
 #endif
+    {
 #if !defined(NO_snprintf) && !defined(NO_vsnprintf)
         (void)snprintf(state->path, len + 1, "%s", (const char *)path);
 #else
         strcpy(state->path, path);
 #endif
+    }
 
     /* compute the flags for open() */
     oflag =
@@ -232,7 +234,7 @@ local gzFile gz_open(const void *path, int fd, const char *mode) {
         state->fd = open((const char *)path, oflag, 0666);
 #ifdef WIDECHAR
     else if (fd == -2)
-        _wsopen_s(&state->fd, path, oflag, _SH_DENYNO, _S_IREAD | _S_IWRITE);
+        state->fd = _wopen(path, oflag, _S_IREAD | _S_IWRITE);
 #endif
     else
         state->fd = fd;
diff --git a/test/example.c b/test/example.c
index e9cb806..d22e5f4 100644
--- a/test/example.c
+++ b/test/example.c
@@ -5,6 +5,10 @@
 
 /* @(#) $Id$ */
 
+#if defined(_WIN32) && !defined(_CRT_SECURE_NO_WARNINGS)
+#  define _CRT_SECURE_NO_WARNINGS
+#endif
+
 #include "zlib.h"
 #include <stdio.h>
 
diff --git a/test/minigzip.c b/test/minigzip.c
index ec86e3f..541f371 100644
--- a/test/minigzip.c
+++ b/test/minigzip.c
@@ -19,6 +19,13 @@
 #  define _POSIX_C_SOURCE 200112L
 #endif
 
+#if defined(_WIN32) && !defined(_CRT_SECURE_NO_WARNINGS)
+#  define _CRT_SECURE_NO_WARNINGS
+#endif
+#if defined(_WIN32) && !defined(_CRT_NONSTDC_NO_DEPRECATE)
+#  define _CRT_NONSTDC_NO_DEPRECATE
+#endif
+
 #include "zlib.h"
 #include <stdio.h>
 
@@ -39,7 +46,7 @@
 #  ifdef UNDER_CE
 #    include <stdlib.h>
 #  endif
-#  define SET_BINARY_MODE(file) _setmode(_fileno(file), O_BINARY)
+#  define SET_BINARY_MODE(file) setmode(fileno(file), O_BINARY)
 #else
 #  define SET_BINARY_MODE(file)
 #endif
@@ -58,10 +65,6 @@
 #if defined(__MWERKS__) && __dest_os != __be_os && __dest_os != __win32_os
 #  include <unix.h> /* for fileno */
 #endif
-#ifdef WIN32
-#  define fileno _fileno
-#  define unlink _unlink
-#endif
 
 #if !defined(Z_HAVE_UNISTD_H) && !defined(_LARGEFILE64_SOURCE)
 #ifndef WIN32 /* unlink already in stdio.h for WIN32 */