Class: Dir

Inherits:
Object show all
Includes:
Enumerable

Overview

Objects of class Dir are directory streams representing directories in the underlying file system. They provide a variety of ways to list directories and their contents. See also File.

The directory used in these examples contains the two regular files (config.h and main.rb), the parent directory (..), and the directory itself (.).

Constant Summary

NS_TMPDIR

Class Method Summary (collapse)

Instance Method Summary (collapse)

Methods included from Enumerable

#_count, #all?, #any?, #collect, #collect_concat, #count, #cycle, #detect, #drop, #drop_while, #each_cons, #each_entry, #each_slice, #each_with_index, #each_with_object, #entries, #find, #find_all, #find_index, #first, #flat_map, #grep, #group_by, #include?, #inject, #map, #max, #max_by, #member?, #min, #min_by, #minmax, #minmax_by, #none?, #one?, #partition, #reduce, #reject, #reverse_each, #select, #sort, #sort_by, #take, #take_while, #to_a, #zip

Constructor Details

- (Dir) new(string)

Returns a new directory object for the named directory.

Returns:

Class Method Details

+ (Array) [](array) + (Array) [](string[, string ...))

Equivalent to calling Dir.glob(array,0) and Dir.glob([string,...],0).

Overloads:

+ (Object) alloc

+ (0) chdir([ string]) + (Object) chdir([ string]) {|path| ... }

Changes the current working directory of the process to the given string. When called without an argument, changes the directory to the value of the environment variable HOME, or LOGDIR. SystemCallError (probably Errno::ENOENT) if the target directory does not exist.

If a block is given, it is passed the name of the new current directory, and the block is executed with that as the current directory. The original working directory is restored when the block exits. The return value of chdir is the value of the block. chdir blocks can be nested, but in a multi-threaded program an error will be raised if a thread attempts to open a chdir block while another thread has one open.

Dir.chdir("/var/spool/mail")
puts Dir.pwd
Dir.chdir("/tmp") do
  puts Dir.pwd
  Dir.chdir("/usr") do
    puts Dir.pwd
  end
  puts Dir.pwd
end
puts Dir.pwd

produces:

/var/spool/mail
/tmp
/usr
/tmp
/var/spool/mail

Overloads:

  • + chdir

    Returns:

    • (0)
  • + chdir {|path| ... }

    Yields:

    • (path)

    Returns:

+ (0) chroot(string)

Changes this process's idea of the file system root. Only a privileged process may make this call. Not available on all platforms. On Unix systems, see chroot(2) for more information.

Returns:

  • (0)

+ (0) delete(string) + (0) rmdir(string) + (0) unlink(string)

Deletes the named directory. Raises a subclass of SystemCallError if the directory isn't empty.

Overloads:

  • + delete

    Returns:

    • (0)
  • + rmdir

    Returns:

    • (0)
  • + unlink

    Returns:

    • (0)

+ (Array) entries(dirname)

Returns an array containing all of the filenames in the given directory. Will raise a SystemCallError if the named directory doesn't exist.

Dir.entries("testdir")   #=> [".", "..", "config.h", "main.rb"]

Returns:

+ (Boolean) exist?

call-seq:

File.directory?(file_name)   ->  true or false

Returns true if the named file is a directory, or a symlink that points at a directory, and false otherwise.

File.directory?(".")

Returns:

  • (Boolean)

+ (Boolean) exists?

call-seq:

File.directory?(file_name)   ->  true or false

Returns true if the named file is a directory, or a symlink that points at a directory, and false otherwise.

File.directory?(".")

Returns:

  • (Boolean)

+ (nil) foreach(dirname) {|filename| ... } + (Enumerator) foreach(dirname)

Calls the block once for each entry in the named directory, passing the filename of each entry as a parameter to the block.

If no block is given, an enumerator is returned instead.

Dir.foreach("testdir") {|x| puts "Got #{x}" }

produces:

Got .
Got ..
Got config.h
Got main.rb

Overloads:

  • + foreach {|filename| ... }

    Yields:

    • (filename)

    Returns:

    • (nil)
  • + foreach

    Returns:

+ (String) getwd + (String) pwd

Returns the path to the current working directory of this process as a string.

Dir.chdir("/tmp")   #=> 0
Dir.getwd           #=> "/tmp"

Overloads:

+ (Array) glob(pattern, [flags]) + (nil) glob(pattern, [flags]) {|filename| ... }

Returns the filenames found by expanding pattern which is an Array of the patterns or the pattern String, either as an array or as parameters to the block. Note that this pattern is not a regexp (it's closer to a shell glob). See File::fnmatch for the meaning of the flags parameter. Note that case sensitivity depends on your system (so File::FNM_CASEFOLD is ignored)

*

Matches any file. Can be restricted by other values in the glob. * will match all files; c* will match all files beginning with c; *c will match all files ending with c; and c will match all files that have c in them (including at the beginning or end). Equivalent to / .* /x in regexp.

**

Matches directories recursively.

?

Matches any one character. Equivalent to /.{1}/ in regexp.

[set]

Matches any one character in set. Behaves exactly like character sets in Regexp, including set negation ([^a-z]).

{p,q}

Matches either literal p or literal q. Matching literals may be more than one character in length. More than two literals may be specified. Equivalent to pattern alternation in regexp.

<code></code>

Escapes the next metacharacter.

 
Dir["config.?"]                     #=> ["config.h"]
Dir.glob("config.?")                #=> ["config.h"]
Dir.glob("*.[a-z][a-z]")            #=> ["main.rb"]
Dir.glob("*.[^r]*")                 #=> ["config.h"]
Dir.glob("*.{rb,h}")                #=> ["main.rb", "config.h"]
Dir.glob("*")                       #=> ["config.h", "main.rb"]
Dir.glob("*", File::FNM_DOTMATCH)   #=> [".", "..", "config.h", "main.rb"]

rbfiles = File.join("**", "*.rb")
Dir.glob(rbfiles)                   #=> ["main.rb",
                                    #    "lib/song.rb",
                                    #    "lib/song/karaoke.rb"]
libdirs = File.join("**", "lib")
Dir.glob(libdirs)                   #=> ["lib"]

librbfiles = File.join("**", "lib", "**", "*.rb")
Dir.glob(librbfiles)                #=> ["lib/song.rb",
                                    #    "lib/song/karaoke.rb"]

librbfiles = File.join("**", "lib", "*.rb")
Dir.glob(librbfiles)                #=> ["lib/song.rb"]

Overloads:

  • + glob

    Returns:

  • + glob {|filename| ... }

    Yields:

    • (filename)

    Returns:

    • (nil)

+ (Object) home + (Object) home("root")

Returns the home directory of the current user or the named user if given.

+ (0) mkdir(string[, integer])

Makes a new directory named by string, with permissions specified by the optional parameter anInteger. The permissions may be modified by the value of File::umask, and are ignored on NT. Raises a SystemCallError if the directory cannot be created. See also the discussion of permissions in the class documentation for File.

Dir.mkdir(File.join(Dir.home, ".foo"), 0700) #=> 0

Returns:

  • (0)

+ (Dir) open(string) + (Object) open(string) {|aDir| ... }

With no block, open is a synonym for Dir::new. If a block is present, it is passed aDir as a parameter. The directory is closed at the end of the block, and Dir::open returns the value of the block.

Overloads:

  • + open

    Returns:

  • + open {|aDir| ... }

    Yields:

    • (aDir)

    Returns:

+ (String) getwd + (String) pwd

Returns the path to the current working directory of this process as a string.

Dir.chdir("/tmp")   #=> 0
Dir.getwd           #=> "/tmp"

Overloads:

+ (0) delete(string) + (0) rmdir(string) + (0) unlink(string)

Deletes the named directory. Raises a subclass of SystemCallError if the directory isn't empty.

Overloads:

  • + delete

    Returns:

    • (0)
  • + rmdir

    Returns:

    • (0)
  • + unlink

    Returns:

    • (0)

+ (0) delete(string) + (0) rmdir(string) + (0) unlink(string)

Deletes the named directory. Raises a subclass of SystemCallError if the directory isn't empty.

Overloads:

  • + delete

    Returns:

    • (0)
  • + rmdir

    Returns:

    • (0)
  • + unlink

    Returns:

    • (0)

Instance Method Details

- (nil) close

Closes the directory stream. Any further attempts to access dir will raise an IOError.

d = Dir.new("testdir")
d.close   #=> nil

Returns:

  • (nil)

- (Dir) each {|filename| ... } - (Enumerator) each

Calls the block once for each entry in this directory, passing the filename of each entry as a parameter to the block.

If no block is given, an enumerator is returned instead.

d = Dir.new("testdir")
d.each  {|x| puts "Got #{x}" }

produces:

Got .
Got ..
Got config.h
Got main.rb

Overloads:

  • - each {|filename| ... }

    Yields:

    • (filename)

    Returns:

  • - each

    Returns:

- (String) inspect

Return a string describing this Dir object.

Returns:

- (String?) path

Returns the path parameter passed to dir's constructor.

d = Dir.new("..")
d.path   #=> ".."

Returns:

- (Integer) pos - (Integer) tell

Returns the current position in dir. See also Dir#seek.

d = Dir.new("testdir")
d.tell   #=> 0
d.read   #=> "."
d.tell   #=> 12

Overloads:

- (Integer) pos(integer)

Synonym for Dir#seek, but returns the position parameter.

d = Dir.new("testdir")   #=> #<Dir:0x401b3c40>
d.read                   #=> "."
i = d.pos                #=> 12
d.read                   #=> ".."
d.pos = i                #=> 12
d.read                   #=> ".."

Returns:

- (String?) read

Reads the next entry from dir and returns it as a string. Returns nil at the end of the stream.

d = Dir.new("testdir")
d.read   #=> "."
d.read   #=> ".."
d.read   #=> "config.h"

Returns:

- (Dir) rewind

Repositions dir to the first entry.

d = Dir.new("testdir")
d.read     #=> "."
d.rewind   #=> #<Dir:0x401b3fb0>
d.read     #=> "."

Returns:

- (Dir) seek(integer)

Seeks to a particular location in dir. integer must be a value returned by Dir#tell.

d = Dir.new("testdir")   #=> #<Dir:0x401b3c40>
d.read                   #=> "."
i = d.tell               #=> 12
d.read                   #=> ".."
d.seek(i)                #=> #<Dir:0x401b3c40>
d.read                   #=> ".."

Returns:

- (Integer) pos - (Integer) tell

Returns the current position in dir. See also Dir#seek.

d = Dir.new("testdir")
d.tell   #=> 0
d.read   #=> "."
d.tell   #=> 12

Overloads: