class Dir
An object of class Dir represents a directory in the underlying file system.
It consists mainly of:
-
A string path, given when the object is created, that specifies a directory in the underlying file system; method
path
returns the path. -
A collection of string entry names, each of which is the name of a directory or file in the underlying file system; the entry names may be retrieved in an array-like fashion or in a stream-like fashion.
About the Examples¶ ↑
Some examples on this page use this simple file tree:
example/ ├── config.h ├── lib/ │ ├── song/ │ │ └── karaoke.rb │ └── song.rb └── main.rb
Others use the file tree for the Ruby project itself.
Dir As Array-Like¶ ↑
A Dir object is in some ways array-like:
-
It has instance methods
children
,each
, andeach_child
. -
It includes module Enumerable.
Dir As Stream-Like¶ ↑
A Dir object is in some ways stream-like.
The stream is initially open for reading, but may be closed manually (using method close
), and will be closed on block exit if created by Dir.open
called with a block. The closed stream may not be further manipulated, and may not be reopened.
The stream has a position, which is the index of an entry in the directory:
-
The initial position is zero (before the first entry).
-
Method
pos=
sets the position (but ignores a value outside the stream), and returns the position. -
Method
seek
is likepos=
, but returnsself
(convenient for chaining). -
Method
read
, if not at end-of-stream, reads the next entry and increments the position; if at end-of-stream, does not increment the position. -
Method
rewind
sets the position to zero.
Examples (using the simple file tree):
dir = Dir.new('example') # => #<Dir:example> dir.pos # => 0 dir.read # => "." dir.read # => ".." dir.read # => "config.h" dir.read # => "lib" dir.read # => "main.rb" dir.pos # => 5 dir.read # => nil dir.pos # => 5 dir.rewind # => #<Dir:example> dir.pos # => 0 dir.pos = 3 # => 3 dir.pos # => 3 dir.seek(4) # => #<Dir:example> dir.pos # => 4 dir.close # => nil dir.read # Raises IOError.
What’s Here¶ ↑
First, what’s elsewhere. Class Dir:
-
Inherits from class Object.
-
Includes module Enumerable, which provides dozens of additional methods.
Here, class Dir provides methods that are useful for:
Reading¶ ↑
-
close
: Closes the directory stream forself
. -
pos=
: Sets the position in the directory stream forself
. -
read
: Reads and returns the next entry in the directory stream forself
. -
rewind
: Sets the position in the directory stream forself
to the first entry. -
seek
: Sets the position in the directory stream forself
the entry at the given offset.
Setting¶ ↑
-
::chdir
: Changes the working directory of the current process to the given directory. -
::chroot
: Changes the file-system root for the current process to the given directory.
Querying¶ ↑
-
::children
: Returns an array of names of the children (both files and directories) of the given directory, but not including.
or..
. -
::empty?
: Returns whether the given path is an empty directory. -
::entries
: Returns an array of names of the children (both files and directories) of the given directory, including.
and..
. -
::exist?
: Returns whether the given path is a directory. -
::getwd
(aliased as pwd): Returns the path to the current working directory. -
::glob
: Returns an array of file paths matching the given pattern and flags. -
::home
: Returns the home directory path for a given user or the current user. -
children
: Returns an array of names of the children (both files and directories) ofself
, but not including.
or..
. -
fileno
: Returns the integer file descriptor forself
. -
path
(aliased asto_path
): Returns the path used to createself
. -
tell
(aliased aspos
): Returns the integer position in the directory stream forself
.
Iterating¶ ↑
-
::each_child
: Calls the given block with each entry in the given directory, but not including.
or..
. -
::foreach
: Calls the given block with each entry in the given directory, including.
and..
. -
each
: Calls the given block with each entry inself
, including.
and..
. -
each_child
: Calls the given block with each entry inself
, but not including.
or..
.
Other¶ ↑
-
::mkdir
: Creates a directory at the given path, with optional permissions. -
::new
: Returns a new Dir for the given path, with optional encoding. -
::open
: Same as::new
, but if a block is given, yields the Dir to the block, closing it upon block exit. -
::unlink
(aliased as::delete
and::rmdir
): Removes the given directory. -
inspect
: Returns a string description ofself
.
Public Class Methods
Calls Dir.glob
with argument patterns
and the values of keyword arguments base
and sort
; returns the array of selected entry names.
# File dir.rb, line 222 def self.[](*args, base: nil, sort: true) Primitive.dir_s_aref(args, base, sort) end
Changes the current working directory.
With argument new_dirpath
and no block, changes to the given dirpath
:
Dir.pwd # => "/example" Dir.chdir('..') # => 0 Dir.pwd # => "/"
With no argument and no block:
-
Changes to the value of environment variable
HOME
if defined. -
Otherwise changes to the value of environment variable
LOGDIR
if defined. -
Otherwise makes no change.
With argument new_dirpath
and a block, temporarily changes the working directory:
-
Calls the block with the argument.
-
Changes to the given directory.
-
Executes the block (yielding the new path).
-
Restores the previous working directory.
-
Returns the block’s return value.
Example:
Dir.chdir('/var/spool/mail') Dir.pwd # => "/var/spool/mail" Dir.chdir('/tmp') do Dir.pwd # => "/tmp" end Dir.pwd # => "/var/spool/mail"
With no argument and a block, calls the block with the current working directory (string) and returns the block’s return value.
Calls to Dir.chdir with blocks may be nested:
Dir.chdir('/var/spool/mail') Dir.pwd # => "/var/spool/mail" Dir.chdir('/tmp') do Dir.pwd # => "/tmp" Dir.chdir('/usr') do Dir.pwd # => "/usr" end Dir.pwd # => "/tmp" end Dir.pwd # => "/var/spool/mail"
In a multi-threaded program an error is raised if a thread attempts to open a chdir
block while another thread has one open, or a call to chdir
without a block occurs inside a block passed to chdir
(even in the same thread).
Raises an exception if the target directory does not exist.
static VALUE dir_s_chdir(int argc, VALUE *argv, VALUE obj) { VALUE path = Qnil; if (rb_check_arity(argc, 0, 1) == 1) { path = rb_str_encode_ospath(rb_get_path(argv[0])); } else { const char *dist = getenv("HOME"); if (!dist) { dist = getenv("LOGDIR"); if (!dist) rb_raise(rb_eArgError, "HOME/LOGDIR not set"); } path = rb_str_new2(dist); } return chdir_path(path, true); }
Returns an array of the entry names in the directory at dirpath
except for '.'
and '..'
; sets the given encoding onto each returned entry name:
Dir.children('/example') # => ["config.h", "lib", "main.rb"] Dir.children('/example').first.encoding # => #<Encoding:UTF-8> Dir.children('/example', encoding: 'US-ASCII').first.encoding # => #<Encoding:US-ASCII>
See String Encoding.
Raises an exception if the directory does not exist.
static VALUE dir_s_children(int argc, VALUE *argv, VALUE io) { VALUE dir; dir = dir_open_dir(argc, argv); return rb_ensure(dir_collect_children, dir, dir_close, dir); }
Changes the root directory of the calling process to that specified in dirpath
. The new root directory is used for pathnames beginning with '/'
. The root directory is inherited by all children of the calling process.
Only a privileged process may call chroot
.
See Linux chroot.
static VALUE dir_s_chroot(VALUE dir, VALUE path) { path = check_dirname(path); if (IO_WITHOUT_GVL_INT(nogvl_chroot, (void *)RSTRING_PTR(path)) == -1) rb_sys_fail_path(path); return INT2FIX(0); }
Removes the directory at dirpath
from the underlying file system:
Dir.rmdir('foo') # => 0
Raises an exception if the directory is not empty.
static VALUE dir_s_rmdir(VALUE obj, VALUE dir) { const char *p; int r; dir = check_dirname(dir); p = RSTRING_PTR(dir); r = IO_WITHOUT_GVL_INT(nogvl_rmdir, (void *)p); if (r < 0) rb_sys_fail_path(dir); return INT2FIX(0); }
Like Dir.foreach
, except that entries '.'
and '..'
are not included.
static VALUE dir_s_each_child(int argc, VALUE *argv, VALUE io) { VALUE dir; RETURN_ENUMERATOR(io, argc, argv); dir = dir_open_dir(argc, argv); rb_ensure(dir_each_child, dir, dir_close, dir); return Qnil; }
Returns whether dirpath
specifies an empty directory:
dirpath = '/tmp/foo' Dir.mkdir(dirpath) Dir.empty?(dirpath) # => true Dir.empty?('/example') # => false Dir.empty?('/example/main.rb') # => false
Raises an exception if dirpath
does not specify a directory or file in the underlying file system.
static VALUE rb_dir_s_empty_p(VALUE obj, VALUE dirname) { VALUE result, orig; const char *path; enum {false_on_notdir = 1}; FilePathValue(dirname); orig = rb_str_dup_frozen(dirname); dirname = rb_str_encode_ospath(dirname); dirname = rb_str_dup_frozen(dirname); path = RSTRING_PTR(dirname); #if defined HAVE_GETATTRLIST && defined ATTR_DIR_ENTRYCOUNT { u_int32_t attrbuf[SIZEUP32(fsobj_tag_t)]; struct attrlist al = {ATTR_BIT_MAP_COUNT, 0, ATTR_CMN_OBJTAG,}; struct getattrlist_args args = GETATTRLIST_ARGS(&al, attrbuf, 0); if (gvl_getattrlist(&args, path) != 0) rb_sys_fail_path(orig); if (*(const fsobj_tag_t *)(attrbuf+1) == VT_HFS) { al.commonattr = 0; al.dirattr = ATTR_DIR_ENTRYCOUNT; if (gvl_getattrlist(&args, path) == 0) { if (attrbuf[0] >= 2 * sizeof(u_int32_t)) return RBOOL(attrbuf[1] == 0); if (false_on_notdir) return Qfalse; } rb_sys_fail_path(orig); } } #endif result = (VALUE)IO_WITHOUT_GVL(nogvl_dir_empty_p, (void *)path); if (FIXNUM_P(result)) { rb_syserr_fail_path((int)FIX2LONG(result), orig); } return result; }
Returns an array of the entry names in the directory at dirpath
; sets the given encoding onto each returned entry name:
Dir.entries('/example') # => ["config.h", "lib", "main.rb", "..", "."] Dir.entries('/example').first.encoding # => #<Encoding:UTF-8> Dir.entries('/example', encoding: 'US-ASCII').first.encoding # => #<Encoding:US-ASCII>
See String Encoding.
Raises an exception if the directory does not exist.
static VALUE dir_entries(int argc, VALUE *argv, VALUE io) { VALUE dir; dir = dir_open_dir(argc, argv); return rb_ensure(dir_collect, dir, dir_close, dir); }
Returns whether dirpath
is a directory in the underlying file system:
Dir.exist?('/example') # => true Dir.exist?('/nosuch') # => false Dir.exist?('/example/main.rb') # => false
Same as File.directory?
.
VALUE rb_file_directory_p(void) { }
Changes the current working directory to the directory specified by the integer file descriptor fd
.
When passing a file descriptor over a UNIX socket or to a child process, using fchdir
instead of chdir
avoids the time-of-check to time-of-use vulnerability
With no block, changes to the directory given by fd
:
Dir.chdir('/var/spool/mail') Dir.pwd # => "/var/spool/mail" dir = Dir.new('/usr') fd = dir.fileno Dir.fchdir(fd) Dir.pwd # => "/usr"
With a block, temporarily changes the working directory:
-
Calls the block with the argument.
-
Changes to the given directory.
-
Executes the block (yields no args).
-
Restores the previous working directory.
-
Returns the block’s return value.
Example:
Dir.chdir('/var/spool/mail') Dir.pwd # => "/var/spool/mail" dir = Dir.new('/tmp') fd = dir.fileno Dir.fchdir(fd) do Dir.pwd # => "/tmp" end Dir.pwd # => "/var/spool/mail"
This method uses the fchdir() function defined by POSIX 2008; the method is not implemented on non-POSIX platforms (raises NotImplementedError
).
Raises an exception if the file descriptor is not valid.
In a multi-threaded program an error is raised if a thread attempts to open a chdir
block while another thread has one open, or a call to chdir
without a block occurs inside a block passed to chdir
(even in the same thread).
static VALUE dir_s_fchdir(VALUE klass, VALUE fd_value) { int fd = RB_NUM2INT(fd_value); if (chdir_alone_block_p()) { struct fchdir_data args; args.old_dir = dir_s_alloc(klass); dir_initialize(NULL, args.old_dir, rb_fstring_cstr("."), Qnil); args.fd = fd; args.done = FALSE; return rb_ensure(fchdir_yield, (VALUE)&args, fchdir_restore, (VALUE)&args); } else { int r = IO_WITHOUT_GVL_INT(nogvl_fchdir, &fd); if (r < 0) rb_sys_fail("fchdir"); } return INT2FIX(0); }
Returns a new Dir object representing the directory specified by the given integer directory file descriptor fd
:
d0 = Dir.new('..') d1 = Dir.for_fd(d0.fileno)
Note that the returned d1
does not have an associated path:
d0.path # => '..' d1.path # => nil
This method uses the fdopendir() function defined by POSIX 2008; the method is not implemented on non-POSIX platforms (raises NotImplementedError
).
static VALUE dir_s_for_fd(VALUE klass, VALUE fd) { struct dir_data *dp; VALUE dir = TypedData_Make_Struct(klass, struct dir_data, &dir_data_type, dp); if (!(dp->dir = IO_WITHOUT_GVL(nogvl_fdopendir, (void *)(VALUE)NUM2INT(fd)))) { rb_sys_fail("fdopendir"); UNREACHABLE_RETURN(Qnil); } RB_OBJ_WRITE(dir, &dp->path, Qnil); return dir; }
Calls the block with each entry name in the directory at dirpath
; sets the given encoding onto each passed entry_name
:
Dir.foreach('/example') {|entry_name| p entry_name }
Output:
"config.h" "lib" "main.rb" ".." "."
Encoding:
Dir.foreach('/example') {|entry_name| p entry_name.encoding; break } Dir.foreach('/example', encoding: 'US-ASCII') {|entry_name| p entry_name.encoding; break }
Output:
#<Encoding:UTF-8> #<Encoding:US-ASCII>
See String Encoding.
Returns an enumerator if no block is given.
static VALUE dir_foreach(int argc, VALUE *argv, VALUE io) { VALUE dir; RETURN_ENUMERATOR(io, argc, argv); dir = dir_open_dir(argc, argv); rb_ensure(dir_each, dir, dir_close, dir); return Qnil; }
Returns the path to the current working directory:
Dir.chdir("/tmp") # => 0 Dir.pwd # => "/tmp"
static VALUE dir_s_getwd(VALUE dir) { return rb_dir_getwd(); }
Forms an array entry_names of the entry names selected by the arguments.
Argument patterns
is a string pattern or an array of string patterns; note that these are not regexps; see below.
Notes for the following examples:
-
'*'
is the pattern that matches any entry name except those that begin with'.'
. -
We use method
Array#take
to shorten returned arrays that otherwise would be very large.
With no block, returns array entry_names; example (using the simple file tree):
Dir.glob('*') # => ["config.h", "lib", "main.rb"]
With a block, calls the block with each of the entry_names and returns nil
:
Dir.glob('*') {|entry_name| puts entry_name } # => nil
Output:
config.h lib main.rb
If optional keyword argument flags
is given, the value modifies the matching; see below.
If optional keyword argument base
is given, its value specifies the base directory. Each pattern string specifies entries relative to the base directory; the default is '.'
. The base directory is not prepended to the entry names in the result:
Dir.glob(pattern, base: 'lib').take(5) # => ["abbrev.gemspec", "abbrev.rb", "base64.gemspec", "base64.rb", "benchmark.gemspec"] Dir.glob(pattern, base: 'lib/irb').take(5) # => ["cmd", "color.rb", "color_printer.rb", "completion.rb", "context.rb"]
If optional keyword sort
is given, its value specifies whether the array is to be sorted; the default is true
. Passing value false
with that keyword disables sorting (though the underlying file system may already have sorted the array).
Patterns
Each pattern string is expanded according to certain metacharacters; examples below use the Ruby file tree:
-
'*'
: Matches any substring in an entry name, similar in meaning to regexp/.*/mx
; may be restricted by other values in the pattern strings:-
'*'
matches all entry names:Dir.glob('*').take(3) # => ["BSDL", "CONTRIBUTING.md", "COPYING"]
-
'c*'
matches entry names beginning with'c'
:Dir.glob('c*').take(3) # => ["CONTRIBUTING.md", "COPYING", "COPYING.ja"]
-
'*c'
matches entry names ending with'c'
:Dir.glob('*c').take(3) # => ["addr2line.c", "array.c", "ast.c"]
-
'*c*'
matches entry names that contain'c'
, even at the beginning or end:Dir.glob('*c*').take(3) # => ["CONTRIBUTING.md", "COPYING", "COPYING.ja"]
Does not match Unix-like hidden entry names (“dot files”). To include those in the matched entry names, use flag IO::FNM_DOTMATCH or something like
'{*,.*}'
. -
-
'**'
: Matches entry names recursively if followed by the slash character'/'
:Dir.glob('**/').take(3) # => ["basictest/", "benchmark/", "benchmark/gc/"]
If the string pattern contains other characters or is not followed by a slash character, it is equivalent to
'*'
. -
'?'
Matches any single character; similar in meaning to regexp/./
:Dir.glob('io.?') # => ["io.c"]
-
'[set]'
: Matches any one character in the string set; behaves like a Regexp character class, including set negation ('[^a-z]'
):Dir.glob('*.[a-z][a-z]').take(3) # => ["CONTRIBUTING.md", "COPYING.ja", "KNOWNBUGS.rb"]
-
'{abc,xyz}'
: Matches either string abc or string xyz; behaves like Regexp alternation:Dir.glob('{LEGAL,BSDL}') # => ["LEGAL", "BSDL"]
More than two alternatives may be given.
-
\
: Escapes the following metacharacter.Note that on Windows, the backslash character may not be used in a string pattern:
Dir['c:\foo*']
will not work, useDir['c:/foo*']
instead.
More examples (using the simple file tree):
# We're in the example directory. File.basename(Dir.pwd) # => "example" 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", "lib", "main.rb"] Dir.glob('*', File::FNM_DOTMATCH) # => [".", "config.h", "lib", "main.rb"] Dir.glob(["*.rb", "*.h"]) # => ["main.rb", "config.h"] Dir.glob('**/*.rb') => ["lib/song/karaoke.rb", "lib/song.rb", "main.rb"] Dir.glob('**/*.rb', base: 'lib') # => ["song/karaoke.rb", "song.rb"] Dir.glob('**/lib') # => ["lib"] Dir.glob('**/lib/**/*.rb') # => ["lib/song/karaoke.rb", "lib/song.rb"] Dir.glob('**/lib/*.rb') # => ["lib/song.rb"]
Flags
If optional keyword argument flags
is given (the default is zero – no flags), its value should be the bitwise OR of one or more of the constants defined in module File::Constants
.
Example:
flags = File::FNM_EXTGLOB | File::FNM_DOTMATCH
Specifying flags can extend, restrict, or otherwise modify the matching.
The flags for this method (other constants in File::Constants
do not apply):
-
File::FNM_DOTMATCH: specifies that entry names beginning with
'.'
should be considered for matching:Dir.glob('*').take(5) # => ["BSDL", "CONTRIBUTING.md", "COPYING", "COPYING.ja", "GPL"] Dir.glob('*', flags: File::FNM_DOTMATCH).take(5) # => [".", ".appveyor.yml", ".cirrus.yml", ".dir-locals.el", ".document"]
-
File::FNM_EXTGLOB: enables the pattern extension
'{a,b}'
, which matches pattern a and pattern b; behaves like a regexp union (e.g.,'(?:a|b)'
):pattern = '{LEGAL,BSDL}' Dir.glob(pattern) # => ["LEGAL", "BSDL"]
-
File::FNM_NOESCAPE: specifies that escaping with the backslash character
'\'
is disabled; the character is not an escape character. -
File::FNM_PATHNAME: specifies that metacharacters
'*'
and'?'
do not match directory separators. -
File::FNM_SHORTNAME: specifies that patterns may match short names if they exist; Windows only.
# File dir.rb, line 410 def self.glob(pattern, _flags = 0, flags: _flags, base: nil, sort: true) Primitive.attr! :use_block Primitive.dir_s_glob(pattern, flags, base, sort) end
Returns the home directory path of the user specified with user_name
if it is not nil
, or the current login user:
Dir.home # => "/home/me" Dir.home('root') # => "/root"
Raises ArgumentError
if user_name
is not a user name.
static VALUE dir_s_home(int argc, VALUE *argv, VALUE obj) { VALUE user; const char *u = 0; rb_check_arity(argc, 0, 1); user = (argc > 0) ? argv[0] : Qnil; if (!NIL_P(user)) { StringValue(user); rb_must_asciicompat(user); u = StringValueCStr(user); if (*u) { return rb_home_dir_of(user, rb_str_new(0, 0)); } } return rb_default_home_dir(rb_str_new(0, 0)); }
Creates a directory in the underlying file system at dirpath
with the given permissions
; returns zero:
Dir.mkdir('foo') File.stat(Dir.new('foo')).mode.to_s(8)[1..4] # => "0755" Dir.mkdir('bar', 0644) File.stat(Dir.new('bar')).mode.to_s(8)[1..4] # => "0644"
See File Permissions. Note that argument permissions
is ignored on Windows.
static VALUE dir_s_mkdir(int argc, VALUE *argv, VALUE obj) { struct mkdir_arg m; VALUE path, vmode; int r; if (rb_scan_args(argc, argv, "11", &path, &vmode) == 2) { m.mode = NUM2MODET(vmode); } else { m.mode = 0777; } path = check_dirname(path); m.path = RSTRING_PTR(path); r = IO_WITHOUT_GVL_INT(nogvl_mkdir, &m); if (r < 0) rb_sys_fail_path(path); return INT2FIX(0); }
Dir.mktmpdir
creates a temporary directory.
require 'tmpdir' Dir.mktmpdir {|dir| # use the directory }
The directory is created with 0700 permission. Application should not change the permission to make the temporary directory accessible from other users.
The prefix and suffix of the name of the directory is specified by the optional first argument, prefix_suffix.
-
If it is not specified or nil, “d” is used as the prefix and no suffix is used.
-
If it is a string, it is used as the prefix and no suffix is used.
-
If it is an array, first element is used as the prefix and second element is used as a suffix.
Dir.mktmpdir {|dir| dir is ".../d..." } Dir.mktmpdir("foo") {|dir| dir is ".../foo..." } Dir.mktmpdir(["foo", "bar"]) {|dir| dir is ".../foo...bar" }
The directory is created under Dir.tmpdir
or the optional second argument tmpdir if non-nil value is given.
Dir.mktmpdir {|dir| dir is "#{Dir.tmpdir}/d..." } Dir.mktmpdir(nil, "/var/tmp") {|dir| dir is "/var/tmp/d..." }
If a block is given, it is yielded with the path of the directory. The directory and its contents are removed using FileUtils.remove_entry
before Dir.mktmpdir
returns. The value of the block is returned.
Dir.mktmpdir {|dir| # use the directory... open("#{dir}/foo", "w") { something using the file } }
If a block is not given, The path of the directory is returned. In this case, Dir.mktmpdir
doesn’t remove the directory.
dir = Dir.mktmpdir begin # use the directory... open("#{dir}/foo", "w") { something using the file } ensure # remove the directory. FileUtils.remove_entry dir end
# File lib/tmpdir.rb, line 99 def self.mktmpdir(prefix_suffix=nil, *rest, **options) base = nil path = Tmpname.create(prefix_suffix || "d", *rest, **options) {|path, _, _, d| base = d mkdir(path, 0700) } if block_given? begin yield path.dup ensure unless base base = File.dirname(path) stat = File.stat(base) if stat.world_writable? and !stat.sticky? raise ArgumentError, "parent directory is world writable but not sticky: #{base}" end end FileUtils.remove_entry path end else path end end
Returns a new Dir object for the directory at dirpath
:
Dir.new('.') # => #<Dir:.>
The value given with optional keyword argument encoding
specifies the encoding for the directory entry names; if nil
(the default), the file system’s encoding is used:
Dir.new('.').read.encoding # => #<Encoding:UTF-8> Dir.new('.', encoding: 'US-ASCII').read.encoding # => #<Encoding:US-ASCII>
# File dir.rb, line 211 def initialize(name, encoding: nil) Primitive.dir_initialize(name, encoding) end
Creates a new Dir object dir for the directory at dirpath
.
With no block, the method equivalent to Dir.new(dirpath, encoding)
:
Dir.open('.') # => #<Dir:.>
With a block given, the block is called with the created dir; on block exit dir is closed and the block’s value is returned:
Dir.open('.') {|dir| dir.inspect } # => "#<Dir:.>"
The value given with optional keyword argument encoding
specifies the encoding for the directory entry names; if nil
(the default), the file system’s encoding is used:
Dir.open('.').read.encoding # => #<Encoding:UTF-8> Dir.open('.', encoding: 'US-ASCII').read.encoding # => #<Encoding:US-ASCII>
# File dir.rb, line 183 def self.open(name, encoding: nil, &block) dir = Primitive.dir_s_open(name, encoding) if block begin yield dir ensure Primitive.dir_s_close(dir) end else dir end end
Returns the path to the current working directory:
Dir.chdir("/tmp") # => 0 Dir.pwd # => "/tmp"
static VALUE dir_s_getwd(VALUE dir) { return rb_dir_getwd(); }
Removes the directory at dirpath
from the underlying file system:
Dir.rmdir('foo') # => 0
Raises an exception if the directory is not empty.
static VALUE dir_s_rmdir(VALUE obj, VALUE dir) { const char *p; int r; dir = check_dirname(dir); p = RSTRING_PTR(dir); r = IO_WITHOUT_GVL_INT(nogvl_rmdir, (void *)p); if (r < 0) rb_sys_fail_path(dir); return INT2FIX(0); }
Returns the operating system’s temporary file path.
require 'tmpdir' Dir.tmpdir # => "/tmp"
# File lib/tmpdir.rb, line 29 def self.tmpdir ['TMPDIR', 'TMP', 'TEMP', ['system temporary path', SYSTMPDIR], ['/tmp']*2, ['.']*2].find do |name, dir| unless dir next if !(dir = ENV[name] rescue next) or dir.empty? end dir = File.expand_path(dir) stat = File.stat(dir) rescue next case when !stat.directory? warn "#{name} is not a directory: #{dir}" when !stat.writable? warn "#{name} is not writable: #{dir}" when stat.world_writable? && !stat.sticky? warn "#{name} is world-writable: #{dir}" else break dir end end or raise ArgumentError, "could not find a temporary directory" end
Removes the directory at dirpath
from the underlying file system:
Dir.rmdir('foo') # => 0
Raises an exception if the directory is not empty.
static VALUE dir_s_rmdir(VALUE obj, VALUE dir) { const char *p; int r; dir = check_dirname(dir); p = RSTRING_PTR(dir); r = IO_WITHOUT_GVL_INT(nogvl_rmdir, (void *)p); if (r < 0) rb_sys_fail_path(dir); return INT2FIX(0); }
Public Instance Methods
Changes the current working directory to self
:
Dir.pwd # => "/" dir = Dir.new('example') dir.chdir Dir.pwd # => "/example"
With a block, temporarily changes the working directory:
-
Calls the block.
-
Changes to the given directory.
-
Executes the block (yields no args).
-
Restores the previous working directory.
-
Returns the block’s return value.
Uses Dir.fchdir
if available, and Dir.chdir
if not, see those methods for caveats.
static VALUE dir_chdir(VALUE dir) { #if defined(HAVE_FCHDIR) && defined(HAVE_DIRFD) && HAVE_FCHDIR && HAVE_DIRFD return dir_s_fchdir(rb_cDir, dir_fileno(dir)); #else return chdir_path(dir_get(dir)->path, false); #endif }
Returns an array of the entry names in self
except for '.'
and '..'
:
dir = Dir.new('/example') dir.children # => ["config.h", "lib", "main.rb"]
static VALUE dir_collect_children(VALUE dir) { VALUE ary = rb_ary_new(); dir_each_entry(dir, rb_ary_push, ary, TRUE); return ary; }
Closes the stream in self
, if it is open, and returns nil
; ignored if self
is already closed:
dir = Dir.new('example') dir.read # => "." dir.close # => nil dir.close # => nil dir.read # Raises IOError.
static VALUE dir_close(VALUE dir) { struct dir_data *dirp; dirp = dir_get(dir); if (!dirp->dir) return Qnil; close_dir_data(dirp); return Qnil; }
Calls the block with each entry name in self
:
Dir.new('example').each {|entry_name| p entry_name }
Output:
"." ".." "config.h" "lib" "main.rb"
With no block given, returns an Enumerator
.
static VALUE dir_each(VALUE dir) { RETURN_ENUMERATOR(dir, 0, 0); return dir_each_entry(dir, dir_yield, Qnil, FALSE); }
Calls the block with each entry name in self
except '.'
and '..'
:
dir = Dir.new('/example') dir.each_child {|entry_name| p entry_name }
Output:
"config.h" "lib" "main.rb"
If no block is given, returns an enumerator.
static VALUE dir_each_child_m(VALUE dir) { RETURN_ENUMERATOR(dir, 0, 0); return dir_each_entry(dir, dir_yield, Qnil, TRUE); }
Returns the file descriptor used in dir.
d = Dir.new('..') d.fileno # => 8
This method uses the dirfd() function defined by POSIX 2008; the method is not implemented on non-POSIX platforms (raises NotImplementedError
).
static VALUE dir_fileno(VALUE dir) { struct dir_data *dirp; int fd; GetDIR(dir, dirp); fd = dirfd(dirp->dir); if (fd == -1) rb_sys_fail("dirfd"); return INT2NUM(fd); }
Returns a string description of self
:
Dir.new('example').inspect # => "#<Dir:example>"
static VALUE dir_inspect(VALUE dir) { struct dir_data *dirp; TypedData_Get_Struct(dir, struct dir_data, &dir_data_type, dirp); if (!NIL_P(dirp->path)) { VALUE str = rb_str_new_cstr("#<"); rb_str_append(str, rb_class_name(CLASS_OF(dir))); rb_str_cat2(str, ":"); rb_str_append(str, dirp->path); rb_str_cat2(str, ">"); return str; } return rb_funcallv(dir, idTo_s, 0, 0); }
Returns the dirpath
string that was used to create self
(or nil
if created by method Dir.for_fd
):
Dir.new('example').path # => "example"
static VALUE dir_path(VALUE dir) { struct dir_data *dirp; TypedData_Get_Struct(dir, struct dir_data, &dir_data_type, dirp); if (NIL_P(dirp->path)) return Qnil; return rb_str_dup(dirp->path); }
Sets the position in self
and returns position
. The value of position
should have been returned from an earlier call to tell
; if not, the return values from subsequent calls to read
are unspecified.
See Dir As Stream-Like.
Examples:
dir = Dir.new('example') dir.pos # => 0 dir.pos = 3 # => 3 dir.pos # => 3 dir.pos = 30 # => 30 dir.pos # => 5
static VALUE dir_set_pos(VALUE dir, VALUE pos) { dir_seek(dir, pos); return pos; }
Reads and returns the next entry name from self
; returns nil
if at end-of-stream; see Dir As Stream-Like:
dir = Dir.new('example') dir.read # => "." dir.read # => ".." dir.read # => "config.h"
static VALUE dir_read(VALUE dir) { struct dir_data *dirp; struct dirent *dp; GetDIR(dir, dirp); rb_errno_set(0); if ((dp = READDIR(dirp->dir, dirp->enc)) != NULL) { return rb_external_str_new_with_enc(dp->d_name, NAMLEN(dp), dirp->enc); } else { int e = errno; if (e != 0) rb_syserr_fail(e, 0); return Qnil; /* end of stream */ } }
Sets the position in self
to zero; see Dir As Stream-Like:
dir = Dir.new('example') dir.read # => "." dir.read # => ".." dir.pos # => 2 dir.rewind # => #<Dir:example> dir.pos # => 0
static VALUE dir_rewind(VALUE dir) { struct dir_data *dirp; GetDIR(dir, dirp); rewinddir(dirp->dir); return dir; }
Sets the position in self
and returns self
. The value of position
should have been returned from an earlier call to tell
; if not, the return values from subsequent calls to read
are unspecified.
See Dir As Stream-Like.
Examples:
dir = Dir.new('example') dir.pos # => 0 dir.seek(3) # => #<Dir:example> dir.pos # => 3 dir.seek(30) # => #<Dir:example> dir.pos # => 5
static VALUE dir_seek(VALUE dir, VALUE pos) { struct dir_data *dirp; long p = NUM2LONG(pos); GetDIR(dir, dirp); seekdir(dirp->dir, p); return dir; }
Returns the current position of self
; see Dir As Stream-Like:
dir = Dir.new('example') dir.tell # => 0 dir.read # => "." dir.tell # => 1
static VALUE dir_tell(VALUE dir) { struct dir_data *dirp; long pos; GetDIR(dir, dirp); if((pos = telldir(dirp->dir)) < 0) rb_sys_fail("telldir"); return rb_int2inum(pos); }