In Files

  • dir.c

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

Dir[ array ] => array click to toggle source
Dir[ string [, string ...] ] => array

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

 
               static VALUE
dir_s_aref(int argc, VALUE *argv, VALUE obj)
 {
    if (argc == 1) {
        return rb_push_glob(argv[0], 0);
    }
    return dir_globs(argc, argv, 0);
 }

/*
 *  call-seq:
 *     Dir.glob( pattern, [flags] ) => array
 *     Dir.glob( pattern, [flags] ) {| filename | block }  => nil
 *
 *  Returns the filenames found by expanding <i>pattern</i> which is
 *  an +Array+ of the patterns or the pattern +String+, either as an
 *  <i>array</i> or as parameters to the block. Note that this pattern
 *  is not a regexp (it's closer to a shell glob). See
 *  <code>File::fnmatch</code> for the meaning of the <i>flags</i>
 *  parameter. Note that case sensitivity depends on your system (so
 *  <code>File::FNM_CASEFOLD</code> is ignored)
 *
 *  <code>*</code>::        Matches any file. Can be restricted by
 *                          other values in the glob. <code>*</code>
 *                          will match all files; <code>c*</code> will
 *                          match all files beginning with
 *                          <code>c</code>; <code>*c</code> will match
 *                          all files ending with <code>c</code>; and
 *                          <code>*c*</code> will match all files that
 *                          have <code>c</code> in them (including at
 *                          the beginning or end). Equivalent to
 *                          <code>/ .* /x</code> in regexp.
 *  <code>**</code>::       Matches directories recursively.
 *  <code>?</code>::        Matches any one character. Equivalent to
 *                          <code>/.{1}/</code> in regexp.
 *  <code>[set]</code>::    Matches any one character in +set+.
 *                          Behaves exactly like character sets in
 *                          Regexp, including set negation
 *                          (<code>[^a-z]</code>).
 *  <code>{p,q}</code>::    Matches either literal <code>p</code> or
 *                          literal <code>q</code>. 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"]
 */
static VALUE
dir_s_glob(argc, argv, obj)
    int argc;
    VALUE *argv;
    VALUE obj;
{
    VALUE str, rflags, ary;
    int flags;

    if (rb_scan_args(argc, argv, "11", &str, &rflags) == 2)
        flags = NUM2INT(rflags);
    else
        flags = 0;

    ary = rb_check_array_type(str);
    if (NIL_P(ary)) {
        ary = rb_push_glob(str, flags);
    }
    else {
        volatile VALUE v = ary;
        ary = dir_globs(RARRAY_LEN(v), RARRAY_PTR(v), flags);
    }

    if (rb_block_given_p()) {
        rb_ary_each(ary);
        return Qnil;
    }
    return ary;
}
            
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.

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(argc, argv, obj)
    int argc;
    VALUE *argv;
    VALUE obj;
{
    VALUE path = Qnil;

    rb_secure(2);
    if (rb_scan_args(argc, argv, "01", &path) == 1) {
        SafeStringValue(path);
    }
    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_block_given_p() || rb_thread_current() != chdir_thread)
            rb_warn("conflicting chdir during another chdir block");
    }

    if (rb_block_given_p()) {
        struct chdir_data args;
        char *cwd = my_getcwd();

        args.old_path = rb_tainted_str_new2(cwd); free(cwd);
        args.new_path = path;
        args.done = Qfalse;
        return rb_ensure(chdir_yield, (VALUE)&args, chdir_restore, (VALUE)&args);
    }
    dir_chdir(path);

    return INT2FIX(0);
}
            
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(dir, path)
    VALUE dir, path;
{
#if defined(HAVE_CHROOT) && !defined(__CHECKER__)
    check_dirname(&path);

    if (chroot(RSTRING(path)->ptr) == -1)
        rb_sys_fail(RSTRING(path)->ptr);

    return INT2FIX(0);
#else
    rb_notimplement();
    return Qnil;                /* not reached */
#endif
}
            
delete( string ) => 0 click to toggle source

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

 
               static VALUE
dir_s_rmdir(obj, dir)
    VALUE obj, dir;
{
    check_dirname(&dir);
    if (rmdir(RSTRING(dir)->ptr) < 0)
        rb_sys_fail(RSTRING(dir)->ptr);

    return INT2FIX(0);
}
            
entries( dirname ) => array click to toggle source

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"]
 
               static VALUE
dir_entries(io, dirname)
    VALUE io, dirname;
{
    VALUE dir;

    dir = dir_open_dir(dirname);
    return rb_ensure(rb_Array, dir, dir_close, dir);
}
            
foreach( dirname ) {| filename | block } => nil click to toggle source

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

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

produces:

Got .
Got ..
Got config.h
Got main.rb
 
               static VALUE
dir_foreach(io, dirname)
    VALUE io, dirname;
{
    VALUE dir;

    RETURN_ENUMERATOR(io, 1, &dirname);
    dir = dir_open_dir(dirname);
    rb_ensure(dir_each, dir, dir_close, dir);
    return Qnil;
}
            
getwd => string click to toggle source

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

Dir.chdir("/tmp")   #=> 0
Dir.getwd           #=> "/tmp"
 
               static VALUE
dir_s_getwd(dir)
    VALUE dir;
{
    char *path;
    VALUE cwd;

    rb_secure(4);
    path = my_getcwd();
    cwd = rb_tainted_str_new2(path);

    free(path);
    return cwd;
}
            
glob( pattern, [flags] ) => array click to toggle source
glob( pattern, [flags] ) {| filename | block } => nil

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"]
 
               static VALUE
dir_s_glob(argc, argv, obj)
    int argc;
    VALUE *argv;
    VALUE obj;
{
    VALUE str, rflags, ary;
    int flags;

    if (rb_scan_args(argc, argv, "11", &str, &rflags) == 2)
        flags = NUM2INT(rflags);
    else
        flags = 0;

    ary = rb_check_array_type(str);
    if (NIL_P(ary)) {
        ary = rb_push_glob(str, flags);
    }
    else {
        volatile VALUE v = ary;
        ary = dir_globs(RARRAY_LEN(v), RARRAY_PTR(v), flags);
    }

    if (rb_block_given_p()) {
        rb_ary_each(ary);
        return Qnil;
    }
    return ary;
}
            
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.

 
               static VALUE
dir_s_mkdir(argc, argv, obj)
    int argc;
    VALUE *argv;
    VALUE obj;
{
    VALUE path, vmode;
    int mode;

    if (rb_scan_args(argc, argv, "11", &path, &vmode) == 2) {
        mode = NUM2INT(vmode);
    }
    else {
        mode = 0777;
    }

    check_dirname(&path);
    if (mkdir(RSTRING(path)->ptr, mode) == -1)
        rb_sys_fail(RSTRING(path)->ptr);

    return INT2FIX(0);
}
            
new( string ) → aDir click to toggle source

Returns a new directory object for the named directory.

 
               static VALUE
dir_initialize(dir, dirname)
    VALUE dir, dirname;
{
    struct dir_data *dp;

    SafeStringValue(dirname);
    Data_Get_Struct(dir, struct dir_data, dp);
    if (dp->dir) closedir(dp->dir);
    if (dp->path) free(dp->path);
    dp->dir = NULL;
    dp->path = NULL;
    dp->dir = opendir(RSTRING(dirname)->ptr);
    if (dp->dir == NULL) {
        if (errno == EMFILE || errno == ENFILE) {
            rb_gc();
            dp->dir = opendir(RSTRING(dirname)->ptr);
        }
        if (dp->dir == NULL) {
            rb_sys_fail(RSTRING(dirname)->ptr);
        }
    }
    dp->path = strdup(RSTRING(dirname)->ptr);

    return dir;
}
            
open( string ) => aDir click to toggle source
open( string ) {| aDir | block } => anObject

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.

 
               static VALUE
dir_s_open(klass, dirname)
    VALUE klass, dirname;
{
    struct dir_data *dp;
    VALUE dir = Data_Make_Struct(klass, struct dir_data, 0, free_dir, dp);

    dir_initialize(dir, dirname);
    if (rb_block_given_p()) {
        return rb_ensure(rb_yield, dir, dir_close, dir);
    }

    return dir;
}
            
pwd => string click to toggle source

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

Dir.chdir("/tmp")   #=> 0
Dir.getwd           #=> "/tmp"
 
               static VALUE
dir_s_getwd(dir)
    VALUE dir;
{
    char *path;
    VALUE cwd;

    rb_secure(4);
    path = my_getcwd();
    cwd = rb_tainted_str_new2(path);

    free(path);
    return cwd;
}
            
rmdir( string ) => 0 click to toggle source

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

 
               static VALUE
dir_s_rmdir(obj, dir)
    VALUE obj, dir;
{
    check_dirname(&dir);
    if (rmdir(RSTRING(dir)->ptr) < 0)
        rb_sys_fail(RSTRING(dir)->ptr);

    return INT2FIX(0);
}
            

Public Instance Methods

close => nil click to toggle source

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

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

    GetDIR(dir, dirp);
    closedir(dirp->dir);
    dirp->dir = NULL;

    return Qnil;
}
            
each { |filename| block } => dir click to toggle source

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

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

produces:

Got .
Got ..
Got config.h
Got main.rb
 
               static VALUE
dir_each(dir)
    VALUE dir;
{
    struct dir_data *dirp;
    struct dirent *dp;

    RETURN_ENUMERATOR(dir, 0, 0);
    GetDIR(dir, dirp);
    rewinddir(dirp->dir);
    for (dp = readdir(dirp->dir); dp != NULL; dp = readdir(dirp->dir)) {
        rb_yield(rb_tainted_str_new(dp->d_name, NAMLEN(dp)));
        if (dirp->dir == NULL) dir_closed();
    }
    return dir;
}
            
inspect => string click to toggle source

Return a string describing this Dir object.

 
               static VALUE
dir_inspect(dir)
    VALUE dir;
{
    struct dir_data *dirp;

    Data_Get_Struct(dir, struct dir_data, dirp);
    if (dirp->path) {
        const char *c = rb_obj_classname(dir);
        int len = strlen(c) + strlen(dirp->path) + 4;
        VALUE s = rb_str_new(0, len);
        snprintf(RSTRING_PTR(s), len+1, "#<%s:%s>", c, dirp->path);
        return s;
    }
    return rb_funcall(dir, rb_intern("to_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(dir)
    VALUE dir;
{
    struct dir_data *dirp;

    Data_Get_Struct(dir, struct dir_data, dirp);
    if (!dirp->path) return Qnil;
    return rb_str_new2(dirp->path);
}
            
pos => 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(dir)
    VALUE dir;
{
#ifdef HAVE_TELLDIR
    struct dir_data *dirp;
    long pos;

    GetDIR(dir, dirp);
    pos = telldir(dirp->dir);
    return rb_int2inum(pos);
#else
    rb_notimplement();
#endif
}
            
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(dir, pos)
    VALUE dir, 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(dir)
    VALUE dir;
{
    struct dir_data *dirp;
    struct dirent *dp;

    GetDIR(dir, dirp);
    errno = 0;
    dp = readdir(dirp->dir);
    if (dp) {
        return rb_tainted_str_new(dp->d_name, NAMLEN(dp));
    }
    else if (errno == 0) {      /* end of stream */
        return Qnil;
    }
    else {
        rb_sys_fail(0);
    }
    return Qnil;                /* not reached */
}
            
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(dir)
    VALUE dir;
{
    struct dir_data *dirp;

    if (rb_safe_level() >= 4 && !OBJ_TAINTED(dir)) {
        rb_raise(rb_eSecurityError, "Insecure: can't close");
    }
    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(dir, pos)
    VALUE dir, pos;
{
    struct dir_data *dirp;
    off_t p = NUM2OFFT(pos);

    GetDIR(dir, dirp);
#ifdef HAVE_SEEKDIR
    seekdir(dirp->dir, p);
    return dir;
#else
    rb_notimplement();
#endif
}
            
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(dir)
    VALUE dir;
{
#ifdef HAVE_TELLDIR
    struct dir_data *dirp;
    long pos;

    GetDIR(dir, dirp);
    pos = telldir(dirp->dir);
    return rb_int2inum(pos);
#else
    rb_notimplement();
#endif
}
            

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