class Dir

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 (.).

Public Class Methods

[](*args, base: nil, sort: true) click to toggle source
Dir[ string [, string ...] [, base: path] [, sort: true] ] -> array

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

# File ruby_3_0_6/dir.rb, line 42
def self.[](*args, base: nil, sort: true)
  Primitive.dir_s_aref(args, base, sort)
end
chdir( [ string] ) → 0 click to toggle source
chdir( [ string] ) {| path | block } → anObject

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 or a call to chdir without a block occurs inside a block passed to chdir (even in the same thread).

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
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);
    }

    if (chdir_blocking > 0) {
        if (rb_thread_current() != chdir_thread)
            rb_raise(rb_eRuntimeError, "conflicting chdir during another chdir block");
        if (!rb_block_given_p())
            rb_warn("conflicting chdir during another chdir block");
    }

    if (rb_block_given_p()) {
        struct chdir_data args;

        args.old_path = rb_str_encode_ospath(rb_dir_getwd());
        args.new_path = path;
        args.done = FALSE;
        return rb_ensure(chdir_yield, (VALUE)&args, chdir_restore, (VALUE)&args);
    }
    else {
        char *p = RSTRING_PTR(path);
        int r = (int)(VALUE)rb_thread_call_without_gvl(nogvl_chdir, p,
                                                        RUBY_UBF_IO, 0);
        if (r < 0)
            rb_sys_fail_path(path);
    }

    return INT2FIX(0);
}
children( dirname ) → array click to toggle source
children( dirname, encoding: enc ) → array

Returns an array containing all of the filenames except for “.” and “..” in the given directory. Will raise a SystemCallError if the named directory doesn’t exist.

The optional encoding keyword argument specifies the encoding of the directory. If not specified, the filesystem encoding is used.

Dir.children("testdir")   #=> ["config.h", "main.rb"]
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);
}
chroot( string ) → 0 click to toggle source

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.

static VALUE
dir_s_chroot(VALUE dir, VALUE path)
{
    path = check_dirname(path);
    if (chroot(RSTRING_PTR(path)) == -1)
        rb_sys_fail_path(path);

    return INT2FIX(0);
}
delete( string ) → 0 click to toggle source
rmdir( string ) → 0
unlink( string ) → 0

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

static VALUE
dir_s_rmdir(VALUE obj, VALUE dir)
{
    const char *p;
    int r;

    dir = check_dirname(dir);
    p = RSTRING_PTR(dir);
    r = (int)(VALUE)rb_thread_call_without_gvl(nogvl_rmdir, (void *)p, RUBY_UBF_IO, 0);
    if (r < 0)
        rb_sys_fail_path(dir);

    return INT2FIX(0);
}
each_child( dirname ) {| filename | block } → nil click to toggle source
each_child( dirname, encoding: enc ) {| filename | block } → nil
each_child( dirname ) → an_enumerator
each_child( dirname, encoding: enc ) → an_enumerator

Calls the block once for each entry except for “.” and “..” 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.each_child("testdir") {|x| puts "Got #{x}" }

produces:

Got config.h
Got main.rb
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;
}
empty?(path_name) → true or false click to toggle source

Returns true if the named file is an empty directory, false if it is not a directory or non-empty.

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,};
        if (getattrlist(path, &al, attrbuf, sizeof(attrbuf), 0) != 0)
            rb_sys_fail_path(orig);
        if (*(const fsobj_tag_t *)(attrbuf+1) == VT_HFS) {
            al.commonattr = 0;
            al.dirattr = ATTR_DIR_ENTRYCOUNT;
            if (getattrlist(path, &al, attrbuf, sizeof(attrbuf), 0) == 0) {
                if (attrbuf[0] >= 2 * sizeof(u_int32_t))
                    return attrbuf[1] ? Qfalse : Qtrue;
                if (false_on_notdir) return Qfalse;
            }
            rb_sys_fail_path(orig);
        }
    }
#endif

    result = (VALUE)rb_thread_call_without_gvl(nogvl_dir_empty_p, (void *)path,
                                            RUBY_UBF_IO, 0);
    if (result == Qundef) {
        rb_sys_fail_path(orig);
    }
    return result;
}
entries( dirname ) → array click to toggle source
entries( dirname, encoding: enc ) → array

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

The optional encoding keyword argument specifies the encoding of the directory. If not specified, the filesystem encoding is used.

Dir.entries("testdir")   #=> [".", "..", "config.h", "main.rb"]
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);
}
exist?(file_name) → true or false click to toggle source

Returns true if the named file is a directory, false otherwise.

VALUE
rb_file_directory_p(void)
{
}
foreach( dirname ) {| filename | block } → nil click to toggle source
foreach( dirname, encoding: enc ) {| filename | block } → nil
foreach( dirname ) → an_enumerator
foreach( dirname, encoding: enc ) → an_enumerator

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
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;
}
getwd → string click to toggle source
pwd → string

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

Dir.chdir("/tmp")   #=> 0
Dir.getwd           #=> "/tmp"
Dir.pwd             #=> "/tmp"
static VALUE
dir_s_getwd(VALUE dir)
{
    return rb_dir_getwd();
}
glob(pattern, _flags = 0, flags: _flags, base: nil, sort: true) click to toggle source
Dir.glob( pattern, [flags], [base: path] [, sort: true] )                       -> array
Dir.glob( pattern, [flags], [base: path] [, sort: true] ) { |filename| block }  -> nil

Expands pattern, which is a pattern string or an Array of pattern strings, and returns an array containing the matching filenames. If a block is given, calls the block once for each matching filename, passing the filename as a parameter to the block.

The optional base keyword argument specifies the base directory for interpreting relative pathnames instead of the current working directory. As the results are not prefixed with the base directory name in this case, you will need to prepend the base directory name if you want real paths.

The results which matched single wildcard or character set are sorted in binary ascending order, unless false is given as the optional sort keyword argument. The order of an Array of pattern strings and braces are preserved.

Note that the pattern is not a regexp, it’s closer to a shell glob. See File::fnmatch for the meaning of the flags parameter. Case sensitivity depends on your system (File::FNM_CASEFOLD is ignored).

*

Matches any file. Can be restricted by other values in the glob. Equivalent to / .* /mx in regexp.

*

Matches all files

c*

Matches all files beginning with c

*c

Matches all files ending with c

*c*

Match all files that have c in them (including at the beginning or end).

Note, this will not match Unix-like hidden files (dotfiles). In order to include those in the match results, you must use the File::FNM_DOTMATCH flag or something like "{*,.*}".

**

Matches directories recursively if followed by /. If this path segment contains any other characters, it is the same as the usual *.

?

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. Equivalent to pattern alternation in regexp.

Matching literals may be more than one character in length. More than two literals may be specified.

\

Escapes the next metacharacter.

Note that this means you cannot use backslash on windows as part of a glob, i.e. Dir["c:\foo*"] will not work, use Dir["c:/foo*"] instead.

Examples:

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"]
Dir.glob(["*.rb", "*.h"])           #=> ["main.rb", "config.h"]

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

Dir.glob("**/*.rb", base: "lib")    #=> ["song.rb",
                                    #    "song/karaoke.rb"]

Dir.glob("**/lib")                  #=> ["lib"]

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

Dir.glob("**/lib/*.rb")             #=> ["lib/song.rb"]
# File ruby_3_0_6/dir.rb, line 133
def self.glob(pattern, _flags = 0, flags: _flags, base: nil, sort: true)
  Primitive.dir_s_glob(pattern, flags, base, sort)
end
home() → "/home/me" click to toggle source
home("root") → "/root"

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

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)) {
        SafeStringValue(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));

}
mkdir( string [, integer] ) → 0 click to toggle source

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
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 = (int)(VALUE)rb_thread_call_without_gvl(nogvl_mkdir, &m, RUBY_UBF_IO, 0);
    if (r < 0)
        rb_sys_fail_path(path);

    return INT2FIX(0);
}
new(name, encoding: nil) click to toggle source
Dir.new( string ) -> aDir
Dir.new( string, encoding: enc ) -> aDir

Returns a new directory object for the named directory.

The optional encoding keyword argument specifies the encoding of the directory. If not specified, the filesystem encoding is used.

# File ruby_3_0_6/dir.rb, line 34
def initialize(name, encoding: nil)
  Primitive.dir_initialize(name, encoding)
end
open(name, encoding: nil) { |dir| ... } click to toggle source
Dir.open( string ) -> aDir
Dir.open( string, encoding: enc ) -> aDir
Dir.open( string ) {| aDir | block } -> anObject
Dir.open( string, encoding: enc ) {| aDir | block } -> anObject

The optional encoding keyword argument specifies the encoding of the directory. If not specified, the filesystem encoding is used.

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.

# File ruby_3_0_6/dir.rb, line 14
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
getwd → string click to toggle source
pwd → string

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

Dir.chdir("/tmp")   #=> 0
Dir.getwd           #=> "/tmp"
Dir.pwd             #=> "/tmp"
static VALUE
dir_s_getwd(VALUE dir)
{
    return rb_dir_getwd();
}
delete( string ) → 0 click to toggle source
rmdir( string ) → 0
unlink( string ) → 0

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

static VALUE
dir_s_rmdir(VALUE obj, VALUE dir)
{
    const char *p;
    int r;

    dir = check_dirname(dir);
    p = RSTRING_PTR(dir);
    r = (int)(VALUE)rb_thread_call_without_gvl(nogvl_rmdir, (void *)p, RUBY_UBF_IO, 0);
    if (r < 0)
        rb_sys_fail_path(dir);

    return INT2FIX(0);
}

Public Instance Methods

children → array click to toggle source

Returns an array containing all of the filenames except for “.” and “..” in this directory.

d = Dir.new("testdir")
d.children   #=> ["config.h", "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;
}
close → nil click to toggle source

Closes the directory stream. Calling this method on closed Dir object is ignored since Ruby 2.3.

d = Dir.new("testdir")
d.close   #=> nil
static VALUE
dir_close(VALUE dir)
{
    struct dir_data *dirp;

    dirp = dir_get(dir);
    if (!dirp->dir) return Qnil;
    closedir(dirp->dir);
    dirp->dir = NULL;

    return Qnil;
}
each { |filename| block } → dir click to toggle source
each → an_enumerator

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
static VALUE
dir_each(VALUE dir)
{
    RETURN_ENUMERATOR(dir, 0, 0);
    return dir_each_entry(dir, dir_yield, Qnil, FALSE);
}
each_child {| filename | block } → dir click to toggle source
each_child → an_enumerator

Calls the block once for each entry except for “.” and “..” 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_child  {|x| puts "Got #{x}" }

produces:

Got config.h
Got main.rb
static VALUE
dir_each_child_m(VALUE dir)
{
    RETURN_ENUMERATOR(dir, 0, 0);
    return dir_each_entry(dir, dir_yield, Qnil, TRUE);
}
fileno → integer click to toggle source

Returns the file descriptor used in dir.

d = Dir.new("..")
d.fileno   #=> 8

This method uses dirfd() function defined by POSIX 2008. NotImplementedError is raised on other platforms, such as Windows, which doesn’t provide the function.

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);
}
inspect → string click to toggle source

Return a string describing this Dir object.

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);
}
path → string or nil click to toggle source

Returns the path parameter passed to dir’s constructor.

d = Dir.new("..")
d.path   #=> ".."
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);
}
Also aliased as: to_path
pos → integer

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

d = Dir.new("testdir")
d.tell   #=> 0
d.read   #=> "."
d.tell   #=> 12
Alias for: tell
pos = integer → integer click to toggle source

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                   #=> ".."
static VALUE
dir_set_pos(VALUE dir, VALUE pos)
{
    dir_seek(dir, pos);
    return pos;
}
read → string or nil click to toggle source

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"
static VALUE
dir_read(VALUE dir)
{
    struct dir_data *dirp;
    struct dirent *dp;

    GetDIR(dir, dirp);
    errno = 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 */
    }
}
rewind → dir click to toggle source

Repositions dir to the first entry.

d = Dir.new("testdir")
d.read     #=> "."
d.rewind   #=> #<Dir:0x401b3fb0>
d.read     #=> "."
static VALUE
dir_rewind(VALUE dir)
{
    struct dir_data *dirp;

    GetDIR(dir, dirp);
    rewinddir(dirp->dir);
    return dir;
}
seek( integer ) → dir click to toggle source

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                   #=> ".."
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;
}
tell → integer click to toggle source

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

d = Dir.new("testdir")
d.tell   #=> 0
d.read   #=> "."
d.tell   #=> 12
static VALUE
dir_tell(VALUE dir)
{
    struct dir_data *dirp;
    long pos;

    GetDIR(dir, dirp);
    pos = telldir(dirp->dir);
    return rb_int2inum(pos);
}
Also aliased as: pos
to_path → string or nil

Returns the path parameter passed to dir’s constructor.

d = Dir.new("..")
d.path   #=> ".."
Alias for: path