# Class: FileSystem

### LuxModule: luxinialuacore

Luxinia used an internal way to gain access to the directory structures that was located in the luxinia.dir function that was undocumented. The function returned a table of filenames. For plattformindependance and other reasons, we decided to use the Lua File System which is part of the Kepler project (http://www.keplerproject.org/luafilesystem/). You can use the lfs lib or this class. This class is a pure wrapper for the lfs lib and provides only additional documentation in the way the other classes are described. The function descriptions are extracts from the lfs documentation that can be found at the given link.

## Methods:

### Method overview:

- attributes
- chdir
- currentdir
- dir
- isDir
- lock
- mkdir
- rmdir
- touch
- unlock

attributes (string filepath, [string attributename])
  returns: ([mixed attributevalues])

  Returns a table with the file attributes corresponding to filepath (or nil followed by an error message in case of error). If the second optional argument is given, then only the value of the named attribute is returned (this use is equivalent to lfs.attributes(filepath).aname, but the table is not created and only one attribute is retrieved from the O.S.). The attributes are described as follows; attribute mode is a string, all the others are numbers, and the time related attributes use the same time reference of os.time:

  1. dev: on Unix systems, this represents the device that the inode resides on.
  On Windows systems, represents the drive number of the disk containing the file
  1. ino: on Unix systems, this represents the inode number. On Windows systems
  this has no meaning mode string representing the associated protection mode (the values could be file, directory, link, socket, named pipe, char device, block device or other)
  1. nlink: number of hard links to the file
  2. uid: user-id of owner (Unix only, always 0 on Windows)
  3. gid: group-id of owner (Unix only, always 0 on Windows)
  4. rdev: on Unix systems, represents the device type, for special file inodes.
  On Windows systems represents the same as dev
  1. access: time of last access
  2. modification: time of last data modification
  3. change: time of last file status change
  4. size: file size, in bytes
  5. blocks: block allocated for file; (Unix only)
  6. blksize: optimal file system I/O blocksize; (Unix only)
chdir (path)
  returns: ([boolean success], [string error])
  Changes the current working directory to the given path. Returns true in case of success or nil plus an error string.
currentdir ()
  returns: ([string dir], [string error])
  Returns a string with the current working directory or nil plus an error string.
dir (string path)
  returns: ([function iterator], [string error])
  Lua iterator over the entries of a given directory. Each time the iterator is called it returns a string with an entry of the directory; nil is returned when there is no more entries. Raises an error if path is not a directory.
isDir (file)
  returns: (boolean isdir)

  return true if the given file is an directory

lock (filehandle, mode[, start[, length] ])
  returns: ([boolean success], [string error])

  Locks a file or a part of it. This function works on open files; the file handle should be specified as the first argument. The string mode could be either r (for a read/shared lock) or w (for a write/exclusive lock). The optional arguments start and length can be used to specify a starting point and its length; both should be numbers.

  Returns true if the operation was successful; in case of error, it returns nil plus an error string.
mkdir (string dirname)
  returns: ([boolean success],[string error])
  Creates a new directory. The argument is the name of the new directory. Returns true if the operation was successful; in case of error, it returns nil plus an error string.
rmdir (string dirname)
  returns: ([boolean success],[string error])
  Removes an existing directory. The argument is the name of the directory. Returns true if the operation was successful; in case of error, it returns nil plus an error string.
touch (string filepath [, atime [, mtime] ])
  returns: ([boolean success],[string error])

  Set access and modification times of a file. This function is a bind to utime function. The first argument is the filename, the second argument (atime) is the access time, and the third argument (mtime) is the modification time. Both times are provided in seconds (which should be generated with Lua standard function os.date). If the modification time is omitted, the access time provided is used; if both times are omitted, the current time is used.

  Returns true if the operation was successful; in case of error, it returns nil plus an error string.
unlock (filehandle[, start[, length] ])
  returns: ([boolean success],[string error])

  Unlocks a file or a part of it. This function works on open files; the file handle should be specified as the first argument. The optional arguments start and length can be used to specify a starting point and its length; both should be numbers.

  Returns true if the operation was successful; in case of error, it returns nil plus an error string.