diff --git a/mongoose.c b/mongoose.c
index fd0e218b..873090cd 100644
--- a/mongoose.c
+++ b/mongoose.c
@@ -803,7 +803,7 @@ int mg_http_upload(struct mg_connection *c, struct mg_http_message *hm,
     snprintf(path, sizeof(path), "%s%c%s", dir, MG_DIRSEP, name);
     LOG(LL_DEBUG,
         ("%p %d bytes @ %d [%s]", c->fd, (int) hm->body.len, (int) oft, name));
-    if ((fp = mg_fopen(path, oft == 0 ? "wb" : "ab")) == NULL) {
+    if ((fp = fopen(path, oft == 0 ? "wb" : "ab")) == NULL) {
       mg_http_reply(c, 400, "", "fopen(%s): %d", name, errno);
       return -2;
     } else {
@@ -926,7 +926,7 @@ void mg_http_serve_file(struct mg_connection *c, struct mg_http_message *hm,
   struct mg_str *inm = mg_http_get_header(hm, "If-None-Match");
   mg_stat_t st;
   char etag[64];
-  FILE *fp = mg_fopen(path, "rb");
+  FILE *fp = fopen(path, "rb");
   if (fp == NULL || mg_stat(path, &st) != 0 ||
       mg_http_etag(etag, sizeof(etag), &st) != etag) {
     LOG(LL_DEBUG, ("404 [%.*s] [%s] %p", (int) hm->uri.len, hm->uri.ptr, path,
@@ -1267,14 +1267,14 @@ void mg_http_serve_dir(struct mg_connection *c, struct mg_http_message *hm,
       mg_http_reply(c, 404, "", "Invalid URI [%.*s]\n", (int) hm->uri.len,
                     hm->uri.ptr);
     } else {
-      FILE *fp = mg_fopen(t2, "r");
+      FILE *fp = fopen(t2, "r");
 #if MG_ENABLE_SSI
       if (is_index && fp == NULL) {
         char *p = t2 + strlen(t2);
         while (p > t2 && p[-1] != '/') p--;
         strncpy(p, "index.shtml", (size_t)(&t2[sizeof(t2)] - p - 2));
         t2[sizeof(t2) - 1] = '\0';
-        fp = mg_fopen(t2, "r");
+        fp = fopen(t2, "r");
       }
 #endif
       if (is_index && fp == NULL) {
@@ -3209,7 +3209,7 @@ void mg_mgr_poll(struct mg_mgr *mgr, int ms) {
 #if MG_ENABLE_SSI
 static char *mg_ssi(const char *path, const char *root, int depth) {
   struct mg_iobuf b = {NULL, 0, 0};
-  FILE *fp = mg_fopen(path, "rb");
+  FILE *fp = fopen(path, "rb");
   if (fp != NULL) {
     char buf[BUFSIZ], arg[sizeof(buf)];
     int ch, intag = 0;
@@ -3921,17 +3921,6 @@ int mg_stat(const char *path, mg_stat_t *st) {
 #endif
 }
 
-FILE *mg_fopen(const char *path, const char *mode) {
-#ifdef _WIN32
-  wchar_t b1[MG_PATH_MAX], b2[10];
-  MultiByteToWideChar(CP_UTF8, 0, path, -1, b1, sizeof(b1) / sizeof(b1[0]));
-  MultiByteToWideChar(CP_UTF8, 0, mode, -1, b2, sizeof(b2) / sizeof(b2[0]));
-  return _wfopen(b1, b2);
-#else
-  return fopen(path, mode);
-#endif
-}
-
 int64_t mg_file_size(const char *path) {
 #if MG_ARCH == MG_ARCH_FREERTOS_TCP && defined(MG_ENABLE_FF)
   struct FF_STAT st;
@@ -3946,7 +3935,7 @@ char *mg_file_read(const char *path, size_t *sizep) {
   FILE *fp;
   char *data = NULL;
   size_t size = (size_t) mg_file_size(path);
-  if ((fp = mg_fopen(path, "rb")) != NULL) {
+  if ((fp = fopen(path, "rb")) != NULL) {
     data = (char *) calloc(1, size + 1);
     if (data != NULL) {
       if (fread(data, 1, size, fp) != size) {
@@ -3967,7 +3956,7 @@ bool mg_file_write(const char *path, const void *buf, size_t len) {
   FILE *fp;
   char tmp[MG_PATH_MAX];
   snprintf(tmp, sizeof(tmp), "%s.%d", path, rand());
-  fp = mg_fopen(tmp, "wb");
+  fp = fopen(tmp, "wb");
   if (fp != NULL) {
     result = fwrite(buf, 1, len, fp) == len;
     fclose(fp);
@@ -4002,7 +3991,7 @@ void mg_random(void *buf, size_t len) {
   while (len--) *p++ = (unsigned char) (esp_random() & 255);
 #elif MG_ARCH == MG_ARCH_WIN32
 #elif MG_ARCH_UNIX && MG_ENABLE_FS
-  FILE *fp = mg_fopen("/dev/urandom", "rb");
+  FILE *fp = fopen("/dev/urandom", "rb");
   if (fp != NULL) {
     if (fread(buf, 1, len, fp) == len) done = true;
     fclose(fp);
diff --git a/mongoose.h b/mongoose.h
index f3b2f43f..2fdc10fb 100644
--- a/mongoose.h
+++ b/mongoose.h
@@ -360,6 +360,7 @@ typedef int socklen_t;
 #define EWOULDBLOCK WSAEWOULDBLOCK
 #endif
 #define realpath(a, b) _fullpath((b), (a), MG_PATH_MAX)
+#define fopen(a, b) mg_fopen((a), (b))
 #ifndef va_copy
 #ifdef __va_copy
 #define va_copy __va_copy
@@ -373,6 +374,13 @@ typedef int socklen_t;
 
 #define MG_INT64_FMT "%I64d"
 
+static __inline FILE *mg_fopen(const char *path, const char *mode) {
+  wchar_t b1[PATH_MAX], b2[10];
+  MultiByteToWideChar(CP_UTF8, 0, path, -1, b1, sizeof(b1) / sizeof(b1[0]));
+  MultiByteToWideChar(CP_UTF8, 0, mode, -1, b2, sizeof(b2) / sizeof(b2[0]));
+  return _wfopen(b1, b2);
+}
+
 // https://lgtm.com/rules/2154840805/ -gmtime, localtime, ctime and asctime
 static __inline struct tm *gmtime_r(time_t *t, struct tm *tm) {
   (void) tm;
@@ -560,7 +568,6 @@ typedef struct _stati64 mg_stat_t;
 typedef struct stat mg_stat_t;
 #endif
 int mg_stat(const char *path, mg_stat_t *);
-FILE *mg_fopen(const char *fp, const char *mode);
 #endif
 
 #define mg_htons(x) mg_ntohs(x)
diff --git a/src/arch_win32.h b/src/arch_win32.h
index a95c1119..f7df817a 100644
--- a/src/arch_win32.h
+++ b/src/arch_win32.h
@@ -67,6 +67,7 @@ typedef int socklen_t;
 #define EWOULDBLOCK WSAEWOULDBLOCK
 #endif
 #define realpath(a, b) _fullpath((b), (a), MG_PATH_MAX)
+#define fopen(a, b) mg_fopen((a), (b))
 #ifndef va_copy
 #ifdef __va_copy
 #define va_copy __va_copy
@@ -80,6 +81,13 @@ typedef int socklen_t;
 
 #define MG_INT64_FMT "%I64d"
 
+static __inline FILE *mg_fopen(const char *path, const char *mode) {
+  wchar_t b1[PATH_MAX], b2[10];
+  MultiByteToWideChar(CP_UTF8, 0, path, -1, b1, sizeof(b1) / sizeof(b1[0]));
+  MultiByteToWideChar(CP_UTF8, 0, mode, -1, b2, sizeof(b2) / sizeof(b2[0]));
+  return _wfopen(b1, b2);
+}
+
 // https://lgtm.com/rules/2154840805/ -gmtime, localtime, ctime and asctime
 static __inline struct tm *gmtime_r(time_t *t, struct tm *tm) {
   (void) tm;
diff --git a/src/http.c b/src/http.c
index cb1d3aea..2f045971 100644
--- a/src/http.c
+++ b/src/http.c
@@ -392,7 +392,7 @@ int mg_http_upload(struct mg_connection *c, struct mg_http_message *hm,
     snprintf(path, sizeof(path), "%s%c%s", dir, MG_DIRSEP, name);
     LOG(LL_DEBUG,
         ("%p %d bytes @ %d [%s]", c->fd, (int) hm->body.len, (int) oft, name));
-    if ((fp = mg_fopen(path, oft == 0 ? "wb" : "ab")) == NULL) {
+    if ((fp = fopen(path, oft == 0 ? "wb" : "ab")) == NULL) {
       mg_http_reply(c, 400, "", "fopen(%s): %d", name, errno);
       return -2;
     } else {
@@ -515,7 +515,7 @@ void mg_http_serve_file(struct mg_connection *c, struct mg_http_message *hm,
   struct mg_str *inm = mg_http_get_header(hm, "If-None-Match");
   mg_stat_t st;
   char etag[64];
-  FILE *fp = mg_fopen(path, "rb");
+  FILE *fp = fopen(path, "rb");
   if (fp == NULL || mg_stat(path, &st) != 0 ||
       mg_http_etag(etag, sizeof(etag), &st) != etag) {
     LOG(LL_DEBUG, ("404 [%.*s] [%s] %p", (int) hm->uri.len, hm->uri.ptr, path,
@@ -856,14 +856,14 @@ void mg_http_serve_dir(struct mg_connection *c, struct mg_http_message *hm,
       mg_http_reply(c, 404, "", "Invalid URI [%.*s]\n", (int) hm->uri.len,
                     hm->uri.ptr);
     } else {
-      FILE *fp = mg_fopen(t2, "r");
+      FILE *fp = fopen(t2, "r");
 #if MG_ENABLE_SSI
       if (is_index && fp == NULL) {
         char *p = t2 + strlen(t2);
         while (p > t2 && p[-1] != '/') p--;
         strncpy(p, "index.shtml", (size_t)(&t2[sizeof(t2)] - p - 2));
         t2[sizeof(t2) - 1] = '\0';
-        fp = mg_fopen(t2, "r");
+        fp = fopen(t2, "r");
       }
 #endif
       if (is_index && fp == NULL) {
diff --git a/src/ssi.c b/src/ssi.c
index e5fb1ee1..7fe3505d 100644
--- a/src/ssi.c
+++ b/src/ssi.c
@@ -9,7 +9,7 @@
 #if MG_ENABLE_SSI
 static char *mg_ssi(const char *path, const char *root, int depth) {
   struct mg_iobuf b = {NULL, 0, 0};
-  FILE *fp = mg_fopen(path, "rb");
+  FILE *fp = fopen(path, "rb");
   if (fp != NULL) {
     char buf[BUFSIZ], arg[sizeof(buf)];
     int ch, intag = 0;
diff --git a/src/util.c b/src/util.c
index 52755abb..2fe80de9 100644
--- a/src/util.c
+++ b/src/util.c
@@ -13,17 +13,6 @@ int mg_stat(const char *path, mg_stat_t *st) {
 #endif
 }
 
-FILE *mg_fopen(const char *path, const char *mode) {
-#ifdef _WIN32
-  wchar_t b1[MG_PATH_MAX], b2[10];
-  MultiByteToWideChar(CP_UTF8, 0, path, -1, b1, sizeof(b1) / sizeof(b1[0]));
-  MultiByteToWideChar(CP_UTF8, 0, mode, -1, b2, sizeof(b2) / sizeof(b2[0]));
-  return _wfopen(b1, b2);
-#else
-  return fopen(path, mode);
-#endif
-}
-
 int64_t mg_file_size(const char *path) {
 #if MG_ARCH == MG_ARCH_FREERTOS_TCP && defined(MG_ENABLE_FF)
   struct FF_STAT st;
@@ -38,7 +27,7 @@ char *mg_file_read(const char *path, size_t *sizep) {
   FILE *fp;
   char *data = NULL;
   size_t size = (size_t) mg_file_size(path);
-  if ((fp = mg_fopen(path, "rb")) != NULL) {
+  if ((fp = fopen(path, "rb")) != NULL) {
     data = (char *) calloc(1, size + 1);
     if (data != NULL) {
       if (fread(data, 1, size, fp) != size) {
@@ -59,7 +48,7 @@ bool mg_file_write(const char *path, const void *buf, size_t len) {
   FILE *fp;
   char tmp[MG_PATH_MAX];
   snprintf(tmp, sizeof(tmp), "%s.%d", path, rand());
-  fp = mg_fopen(tmp, "wb");
+  fp = fopen(tmp, "wb");
   if (fp != NULL) {
     result = fwrite(buf, 1, len, fp) == len;
     fclose(fp);
@@ -94,7 +83,7 @@ void mg_random(void *buf, size_t len) {
   while (len--) *p++ = (unsigned char) (esp_random() & 255);
 #elif MG_ARCH == MG_ARCH_WIN32
 #elif MG_ARCH_UNIX && MG_ENABLE_FS
-  FILE *fp = mg_fopen("/dev/urandom", "rb");
+  FILE *fp = fopen("/dev/urandom", "rb");
   if (fp != NULL) {
     if (fread(buf, 1, len, fp) == len) done = true;
     fclose(fp);
diff --git a/src/util.h b/src/util.h
index 3bbc5cee..b436310c 100644
--- a/src/util.h
+++ b/src/util.h
@@ -44,7 +44,6 @@ typedef struct _stati64 mg_stat_t;
 typedef struct stat mg_stat_t;
 #endif
 int mg_stat(const char *path, mg_stat_t *);
-FILE *mg_fopen(const char *fp, const char *mode);
 #endif
 
 #define mg_htons(x) mg_ntohs(x)