diff --git a/include/coreinit/filesystem.h b/include/coreinit/filesystem.h
index 72949636..d22ca2a8 100644
--- a/include/coreinit/filesystem.h
+++ b/include/coreinit/filesystem.h
@@ -193,6 +193,16 @@ typedef enum FSMountSourceType {
     FS_MOUNT_SOURCE_UNK = 1,
 } FSMountSourceType;
 
+typedef enum FSOpenFileFlags
+{
+   //! Open file normally
+   FS_OPEN_FLAG_NONE = (0 << 0),
+   //! Open (new) unencrypted file. Used for vWii files since it allows for direct access without the Wii U filesystem through it's block address.
+   FS_OPEN_FLAG_UNENCRYPTED = (1 << 0),
+   //! Preallocates new file size using given size
+   FS_OPEN_FLAG_PREALLOC_SIZE = (1 << 1)
+} FSOpenFileFlags;
+
 typedef void(*FSAsyncCallback)(FSClient *, FSCmdBlock *, FSStatus, uint32_t);
 typedef void(*FSStateChangeCallback)(FSClient *, FSVolumeState, void *);
 
@@ -562,6 +572,29 @@ FSCloseFileAsync(FSClient *client,
                  FSErrorFlag errorMask,
                  FSAsyncData *asyncData);
 
+FSStatus
+FSOpenFileEx(FSClient *client,
+             FSCmdBlock *block,
+             const char *path,
+             const char *mode,
+             FSMode createMode,
+             FSOpenFileFlags openFlag,
+             uint32_t preallocSize,
+             FSFileHandle *handle,
+             FSErrorFlag errorMask);
+
+FSStatus
+FSOpenFileExAsync(FSClient *client,
+                  FSCmdBlock *block,
+                  const char *path,
+                  const char *mode,
+                  FSFileHandle *outHandle,
+                  FSMode createMode,
+                  FSOpenFileFlags openFlag,
+                  uint32_t preallocSize,
+                  FSErrorFlag errorMask,
+                  FSAsyncData *asyncData);
+
 FSStatus
 FSOpenDir(FSClient *client,
           FSCmdBlock *block,
diff --git a/include/coreinit/filesystem_fsa.h b/include/coreinit/filesystem_fsa.h
index bf3c175c..06485655 100644
--- a/include/coreinit/filesystem_fsa.h
+++ b/include/coreinit/filesystem_fsa.h
@@ -280,15 +280,6 @@ WUT_CHECK_OFFSET(FSAClientAttachAsyncData, 0x04, userContext);
 WUT_CHECK_OFFSET(FSAClientAttachAsyncData, 0x08, ioMsgQueue);
 WUT_CHECK_SIZE(FSAClientAttachAsyncData, 0xC);
 
-typedef enum FSOpenFileFlags {
-    //! Open file normally
-    FS_OPEN_FLAG_NONE = (0 << 0),
-    //! Open (new) encrypted file
-    FS_OPEN_FLAG_ENCRYPTED = (1 << 0),
-    //! Preallocates new file size using given size
-    FS_OPEN_FLAG_PREALLOC_SIZE = (1 << 1)
-} FSOpenFileFlags;
-
 /**
  * Block information.
  */
@@ -392,12 +383,6 @@ FSAChangeMode(FSAClientHandle client,
               const char *path,
               FSMode permission);
 
-FSError
-FSOpenFileEx(FSAClientHandle client,
-             const char *path,
-             const char *mode,
-             FSAFileHandle *outFileHandle);
-
 FSError
 FSAOpenFileEx(FSAClientHandle client,
               const char *path,
diff --git a/libraries/wutdevoptab/devoptab_fs.h b/libraries/wutdevoptab/devoptab_fs.h
index 67ed4835..05f2169f 100644
--- a/libraries/wutdevoptab/devoptab_fs.h
+++ b/libraries/wutdevoptab/devoptab_fs.h
@@ -83,4 +83,6 @@ int       __wut_fs_utimes(struct _reent *r, const char *filename, const struct t
 char *    __wut_fs_fixpath(struct _reent *r, const char *path);
 int       __wut_fs_translate_error(FSStatus error);
 time_t    __wut_fs_translate_time(FSTime timeValue);
-mode_t    __wut_fs_translate_mode(FSStat fileStat);
+mode_t    __wut_fs_translate_stat_mode(FSStat *fsStat);
+FSMode    __wut_fs_translate_permission_mode(mode_t mode);
+void      __wut_fs_translate_stat(FSStat *fsStat, struct stat* posStat);
diff --git a/libraries/wutdevoptab/devoptab_fs_chmod.c b/libraries/wutdevoptab/devoptab_fs_chmod.c
index bc4de68a..a644d2f6 100644
--- a/libraries/wutdevoptab/devoptab_fs_chmod.c
+++ b/libraries/wutdevoptab/devoptab_fs_chmod.c
@@ -1,13 +1,6 @@
 #include <sys/stat.h>
 #include "devoptab_fs.h"
 
-static inline FSMode
-__wut_fs_convert_mode(mode_t mode)
-{
-   // Convert normal Unix octal permission bits into CafeOS hexadecimal permission bits
-   return (FSMode) (((mode & S_IRWXU) << 2) | ((mode & S_IRWXG) << 1) | (mode & S_IRWXO));
-}
-
 int
 __wut_fs_chmod(struct _reent *r,
                const char *path,
@@ -26,7 +19,7 @@ __wut_fs_chmod(struct _reent *r,
       return -1;
    }
 
-   FSMode translatedMode = __wut_fs_convert_mode(mode);
+   FSMode translatedMode = __wut_fs_translate_permission_mode(mode);
 
    FSInitCmdBlock(&cmd);
    status = FSChangeMode(__wut_devoptab_fs_client, &cmd, fixedPath,
diff --git a/libraries/wutdevoptab/devoptab_fs_dirnext.c b/libraries/wutdevoptab/devoptab_fs_dirnext.c
index 83f57b78..e145516d 100644
--- a/libraries/wutdevoptab/devoptab_fs_dirnext.c
+++ b/libraries/wutdevoptab/devoptab_fs_dirnext.c
@@ -25,19 +25,7 @@ __wut_fs_dirnext(struct _reent *r,
       return -1;
    }
 
-   // Fill in the stat info
-   memset(filestat, 0, sizeof(struct stat));
-   filestat->st_ino = 0;
-
-   if (dir->entry_data.info.flags & FS_STAT_DIRECTORY) {
-      filestat->st_mode = S_IFDIR;
-   } else {
-      filestat->st_mode = S_IFREG;
-   }
-
-   filestat->st_uid = dir->entry_data.info.owner;
-   filestat->st_gid = dir->entry_data.info.group;
-   filestat->st_size = dir->entry_data.info.size;
+   __wut_fs_translate_stat(&dir->entry_data.info, filestat);
 
    memset(filename, 0, NAME_MAX);
    strcpy(filename, dir->entry_data.name);
diff --git a/libraries/wutdevoptab/devoptab_fs_fstat.c b/libraries/wutdevoptab/devoptab_fs_fstat.c
index 95d1eb8a..78fa880c 100644
--- a/libraries/wutdevoptab/devoptab_fs_fstat.c
+++ b/libraries/wutdevoptab/devoptab_fs_fstat.c
@@ -24,15 +24,7 @@ __wut_fs_fstat(struct _reent *r,
       return -1;
    }
 
-   memset(st, 0, sizeof(struct stat));
-   st->st_size  = fsStat.size;
-   st->st_uid   = fsStat.owner;
-   st->st_gid   = fsStat.group;
-   st->st_nlink = 1;
-   st->st_mode  = __wut_fs_translate_mode(fsStat);
-   st->st_atime = __wut_fs_translate_time(fsStat.modified);
-   st->st_ctime = __wut_fs_translate_time(fsStat.created);
-   st->st_mtime = __wut_fs_translate_time(fsStat.modified);
+   __wut_fs_translate_stat(&fsStat, st);
 
    return 0;
 }
diff --git a/libraries/wutdevoptab/devoptab_fs_open.c b/libraries/wutdevoptab/devoptab_fs_open.c
index c6628527..4888d70e 100644
--- a/libraries/wutdevoptab/devoptab_fs_open.c
+++ b/libraries/wutdevoptab/devoptab_fs_open.c
@@ -1,5 +1,8 @@
 #include "devoptab_fs.h"
 
+// Extended "magic" value that allows opening files with FS_OPEN_FLAG_UNENCRYPTED in underlying FSOpenFileEx() call similar to O_DIRECTORY
+#define O_UNENCRYPTED 0x4000000
+
 int
 __wut_fs_open(struct _reent *r,
               void *fileStruct,
@@ -19,32 +22,34 @@ __wut_fs_open(struct _reent *r,
    }
 
    // Map flags to open modes
-   if (flags == 0) {
+   int commonFlagMask = O_CREAT | O_TRUNC | O_APPEND;
+   if (((flags & O_ACCMODE) == O_RDONLY) && !(flags & commonFlagMask)) {
       fsMode = "r";
-   } else if (flags == 2) {
+   } else if (((flags & O_ACCMODE) == O_RDWR) && !(flags & commonFlagMask)) {
       fsMode = "r+";
-   } else if (flags == 0x601) {
+   } else if (((flags & O_ACCMODE) == O_WRONLY) && ((flags & commonFlagMask) == (O_CREAT | O_TRUNC))) {
       fsMode = "w";
-   } else if(flags == 0x602) {
+   } else if (((flags & O_ACCMODE) == O_RDWR) && ((flags & commonFlagMask) == (O_CREAT | O_TRUNC))) {
       fsMode = "w+";
-   } else if(flags == 0x209) {
+   } else if (((flags & O_ACCMODE) == O_WRONLY) && ((flags & commonFlagMask) == (O_CREAT | O_APPEND))) {
       fsMode = "a";
-   } else if(flags == 0x20A) {
+   } else if (((flags & O_ACCMODE) == O_RDWR) && ((flags & commonFlagMask) == (O_CREAT | O_APPEND))) {
       fsMode = "a+";
    } else {
       r->_errno = EINVAL;
       return -1;
    }
 
-   char *fixedPath = __wut_fs_fixpath(r,path);
+   char *fixedPath = __wut_fs_fixpath(r, path);
    if (!fixedPath) {
       return -1;
    }
 
    // Open the file
    FSInitCmdBlock(&cmd);
-   status = FSOpenFile(__wut_devoptab_fs_client, &cmd, fixedPath, fsMode, &fd,
-                       FS_ERROR_FLAG_ALL);
+   FSOpenFileFlags openFlags = (mode & O_UNENCRYPTED) ? FS_OPEN_FLAG_UNENCRYPTED : FS_OPEN_FLAG_NONE;
+   uint32_t preallocSize = 0;
+   status = FSOpenFileEx(__wut_devoptab_fs_client, &cmd, fixedPath, fsMode, __wut_fs_translate_permission_mode(mode), openFlags, preallocSize, &fd, FS_ERROR_FLAG_ALL);
    free(fixedPath);
    if (status < 0) {
       r->_errno = __wut_fs_translate_error(status);
@@ -54,6 +59,14 @@ __wut_fs_open(struct _reent *r,
    file = (__wut_fs_file_t *)fileStruct;
    file->fd = fd;
    file->flags = (flags & (O_ACCMODE|O_APPEND|O_SYNC));
-   FSGetPosFile(__wut_devoptab_fs_client, &cmd, fd, &file->offset, FS_ERROR_FLAG_ALL);
+   if (flags & O_APPEND) {
+      status = FSGetPosFile(__wut_devoptab_fs_client, &cmd, fd, &file->offset, FS_ERROR_FLAG_ALL);
+      if (status < 0) {
+         FSCloseFile(__wut_devoptab_fs_client, &cmd, fd, FS_ERROR_FLAG_ALL);
+         r->_errno = __wut_fs_translate_error(status);
+         return -1;
+      }
+   }
+
    return 0;
 }
diff --git a/libraries/wutdevoptab/devoptab_fs_rmdir.c b/libraries/wutdevoptab/devoptab_fs_rmdir.c
index 70b89eb6..0c252681 100644
--- a/libraries/wutdevoptab/devoptab_fs_rmdir.c
+++ b/libraries/wutdevoptab/devoptab_fs_rmdir.c
@@ -21,7 +21,7 @@ __wut_fs_rmdir(struct _reent *r,
    status = FSRemove(__wut_devoptab_fs_client, &cmd, fixedPath, FS_ERROR_FLAG_ALL);
    free(fixedPath);
    if (status < 0) {
-      r->_errno = __wut_fs_translate_error(status);
+      r->_errno = status == FS_STATUS_EXISTS ? ENOTEMPTY : __wut_fs_translate_error(status);
       return -1;
    }
 
diff --git a/libraries/wutdevoptab/devoptab_fs_stat.c b/libraries/wutdevoptab/devoptab_fs_stat.c
index 1ad8c41b..9a189305 100644
--- a/libraries/wutdevoptab/devoptab_fs_stat.c
+++ b/libraries/wutdevoptab/devoptab_fs_stat.c
@@ -20,7 +20,6 @@ __wut_fs_stat(struct _reent *r,
 
    FSInitCmdBlock(&cmd);
 
-   // First try open as file
    status = FSGetStat(__wut_devoptab_fs_client, &cmd, fixedPath, &fsStat, FS_ERROR_FLAG_ALL);
    if (status < 0) {
       free(fixedPath);
@@ -29,19 +28,7 @@ __wut_fs_stat(struct _reent *r,
    }
    free(fixedPath);
 
-   memset(st, 0, sizeof(struct stat));
-
-   st->st_nlink = 1;
-   st->st_atime = __wut_fs_translate_time(fsStat.modified);
-   st->st_ctime = __wut_fs_translate_time(fsStat.created);
-   st->st_mtime = __wut_fs_translate_time(fsStat.modified);
-   st->st_mode = __wut_fs_translate_mode(fsStat);
-
-   if (!(fsStat.flags & FS_STAT_DIRECTORY)) {
-      st->st_size = fsStat.size;
-      st->st_uid = fsStat.owner;
-      st->st_gid = fsStat.group;
-   }
+   __wut_fs_translate_stat(&fsStat, st);
 
    return 0;
 }
\ No newline at end of file
diff --git a/libraries/wutdevoptab/devoptab_fs_unlink.c b/libraries/wutdevoptab/devoptab_fs_unlink.c
index ae0c0da9..d53c6ec4 100644
--- a/libraries/wutdevoptab/devoptab_fs_unlink.c
+++ b/libraries/wutdevoptab/devoptab_fs_unlink.c
@@ -22,7 +22,7 @@ __wut_fs_unlink(struct _reent *r,
    status = FSRemove(__wut_devoptab_fs_client, &cmd, fixedPath, FS_ERROR_FLAG_ALL);
    free(fixedPath);
    if (status < 0) {
-      r->_errno = __wut_fs_translate_error(status);
+      r->_errno = status == FS_STATUS_EXISTS ? EISDIR : __wut_fs_translate_error(status);
       return -1;
    }
 
diff --git a/libraries/wutdevoptab/devoptab_fs_utils.c b/libraries/wutdevoptab/devoptab_fs_utils.c
index 3ac326f6..bc2b5f91 100644
--- a/libraries/wutdevoptab/devoptab_fs_utils.c
+++ b/libraries/wutdevoptab/devoptab_fs_utils.c
@@ -17,12 +17,19 @@ __wut_fs_fixpath(struct _reent *r,
       p = (char *) path;
    }
 
-   if (strlen(p) > PATH_MAX) {
+   size_t pathLength = strlen(p);
+   if (pathLength > FS_MAX_PATH) {
       r->_errno = ENAMETOOLONG;
       return NULL;
    }
 
-   fixedPath = memalign(0x40, PATH_MAX + 1);
+   // wii u softlocks on empty strings so give expected error back
+   if (pathLength == 0) {
+      r->_errno = ENOENT;
+      return NULL;
+   }
+
+   fixedPath = memalign(0x40, FS_MAX_PATH + 1);
    if (!fixedPath) {
       r->_errno = ENOMEM;
       return NULL;
@@ -33,35 +40,56 @@ __wut_fs_fixpath(struct _reent *r,
    return fixedPath;
 }
 
-mode_t __wut_fs_translate_mode(FSStat fileStat) {
+mode_t __wut_fs_translate_stat_mode(FSStat* fsStat) {
    mode_t retMode = 0;
 
-   if ((fileStat.flags & FS_STAT_LINK) == FS_STAT_LINK) {
+   if ((fsStat->flags & FS_STAT_LINK) == FS_STAT_LINK) {
       retMode |= S_IFLNK;
-   } else if ((fileStat.flags & FS_STAT_DIRECTORY) == FS_STAT_DIRECTORY) {
+   } else if ((fsStat->flags & FS_STAT_DIRECTORY) == FS_STAT_DIRECTORY) {
       retMode |= S_IFDIR;
-   } else if ((fileStat.flags & FS_STAT_FILE) == FS_STAT_FILE) {
+   } else if ((fsStat->flags & FS_STAT_FILE) == FS_STAT_FILE) {
       retMode |= S_IFREG;
-   } else if(fileStat.size == 0) {
+   } else if (fsStat->size == 0) {
       // Mounted paths like /vol/external01 have no flags set.
       // If no flag is set and the size is 0, it's a (root) dir
       retMode |= S_IFDIR;
-   }  else if (fileStat.size > 0) {
+   }  else if (fsStat->size > 0) {
       // Some regular Wii U files have no type info but will have a size
       retMode |= S_IFREG;
    }
 
-   mode_t ownerFlags = (fileStat.mode & (FS_MODE_READ_OWNER | FS_MODE_WRITE_OWNER | FS_MODE_EXEC_OWNER)) >> 2;
-   mode_t groupFlags = (fileStat.mode & (FS_MODE_READ_GROUP | FS_MODE_WRITE_GROUP | FS_MODE_EXEC_GROUP)) >> 1;
-   mode_t userFlags = (fileStat.mode & (FS_MODE_READ_OTHER | FS_MODE_WRITE_OTHER | FS_MODE_EXEC_OTHER));
+   // Convert normal CafeOS hexadecimal permission bits into Unix octal permission bits
+   mode_t permissionMode = (((fsStat->mode >> 2) & S_IRWXU) | ((fsStat->mode >> 1) & S_IRWXG) | (fsStat->mode & S_IRWXO));
 
-   return retMode | ownerFlags | groupFlags | userFlags;
+   return retMode | permissionMode;
+}
+
+FSMode __wut_fs_translate_permission_mode(mode_t mode) {
+   // Convert normal Unix octal permission bits into CafeOS hexadecimal permission bits
+   return (FSMode) (((mode & S_IRWXU) << 2) | ((mode & S_IRWXG) << 1) | (mode & S_IRWXO));
 }
 
 time_t __wut_fs_translate_time(FSTime timeValue) {
    return (timeValue /1000000) + EPOCH_DIFF_SECS(WIIU_FSTIME_EPOCH_YEAR);
 }
 
+void __wut_fs_translate_stat(FSStat* fsStat, struct stat* posStat) {
+   memset(posStat, 0, sizeof(struct stat));
+   posStat->st_dev = (dev_t)__wut_devoptab_fs_client;
+   posStat->st_ino = fsStat->entryId;
+   posStat->st_mode = __wut_fs_translate_stat_mode(fsStat);
+   posStat->st_nlink = 1;
+   posStat->st_uid = fsStat->owner;
+   posStat->st_gid = fsStat->group;
+   posStat->st_rdev = posStat->st_dev;
+   posStat->st_size = fsStat->size;
+   posStat->st_atime = __wut_fs_translate_time(fsStat->modified);
+   posStat->st_ctime = __wut_fs_translate_time(fsStat->created);
+   posStat->st_mtime = __wut_fs_translate_time(fsStat->modified);
+   posStat->st_blksize = 512;
+   posStat->st_blocks = (posStat->st_size + posStat->st_blksize - 1) / posStat->st_size;
+}
+
 int
 __wut_fs_translate_error(FSStatus error) {
    switch ((int) error) {