Class: File

Inherits:
IO show all
Defined in:
file.c

Overview

A File is an abstraction of any file object accessible by the program and is closely associated with class IO File includes the methods of module FileTest as class methods, allowing you to write (for example) File.exist?("foo").

In the description of File methods, permission bits are a platform-specific set of bits that indicate permissions of a file. On Unix-based systems, permissions are viewed as a set of three octets, for the owner, the group, and the rest of the world. For each of these entities, permissions may be set to read, write, or execute the file:

The permission bits 0644 (in octal) would thus be interpreted as read/write for owner, and read-only for group and other. Higher-order bits may also be used to indicate the type of file (plain, directory, pipe, socket, and so on) and various other special features. If the permissions are for a directory, the meaning of the execute bit changes; when set the directory can be searched.

On non-Posix operating systems, there may be only the ability to make a file read-only or read-write. In this case, the remaining permission bits will be synthesized to resemble typical values. For instance, on Windows NT the default permission bits are 0644, which means read/write for owner, read-only for all others. The only change that can be made is to make the file read-only, which is reported as 0444.

Defined Under Namespace

Modules: Constants Classes: Stat

Constant Summary collapse

Separator =
separator
SEPARATOR =
separator
ALT_SEPARATOR =
Qnil
PATH_SEPARATOR =
rb_obj_freeze(rb_str_new2(PATH_SEP))

Constants inherited from IO

IO::SEEK_CUR, IO::SEEK_END, IO::SEEK_SET

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from IO

#<<, #advise, #autoclose=, #autoclose?, #binmode, #binmode?, binread, binwrite, #bytes, #chars, #close, #close_on_exec=, #close_on_exec?, #close_read, #close_write, #closed?, #codepoints, copy_stream, #each, #each_byte, #each_char, #each_codepoint, #each_line, #eof, #eof?, #external_encoding, #fcntl, #fdatasync, #fileno, #flush, for_fd, foreach, #fsync, #getbyte, #getc, #gets, #initialize_copy, #inspect, #internal_encoding, #ioctl, #isatty, #lineno, #lineno=, #lines, new, #pid, pipe, popen, #pos, #pos=, #print, #printf, #putc, #puts, read, #read, #read_nonblock, #readbyte, #readchar, #readline, #readlines, readlines, #readpartial, #reopen, #rewind, #seek, select, #set_encoding, #stat, #sync, #sync=, sysopen, #sysread, #sysseek, #syswrite, #tell, #to_io, try_convert, #tty?, #ungetbyte, #ungetc, #write, write, #write_nonblock

Methods included from Enumerable

#all?, #any?, #chunk, #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, #slice_before, #sort, #sort_by, #take, #take_while, #to_a, #zip

Constructor Details

#new(filename, mode = "r"[, opt]) ⇒ File #new(filename[, mode [, perm]][, opt]) ⇒ File

Opens the file named by filename according to mode (default is "r") and returns a new File object.

Parameters

See the description of class IO for a description of mode. The file mode may optionally be specified as a Fixnum by or-ing together the flags (O_RDONLY etc, again described under IO).

Optional permission bits may be given in perm. These mode and permission bits are platform dependent; on Unix systems, see open(2) for details.

Optional opt parameter is same as in IO.open.

Examples

f = File.new("testfile", "r")
f = File.new("newfile",  "w+")
f = File.new("newfile", File::CREAT|File::TRUNC|File::RDWR, 0644)

Overloads:

  • #new(filename, mode = "r"[, opt]) ⇒ File
  • #new(filename[, mode [, perm]][, opt]) ⇒ File

# File 'io.c'

static VALUE
rb_file_initialize(int argc, VALUE *argv, VALUE io)
{
if (RFILE(io)->fptr) {
rb_raise(rb_eRuntimeError, "reinitializing File");
}

Class Method Details

.absolute_path(file_name[, dir_string]) ⇒ Object

Converts a pathname to an absolute pathname. Relative paths are referenced from the current working directory of the process unless dir_string is given, in which case it will be used as the starting point. If the given pathname starts with a "~'' it is NOT expanded, it is treated as a normal directory name.

File.absolute_path("~oracle/bin")       #=> "<relative_path>/~oracle/bin"

# File 'file.c'

VALUE
rb_file_s_absolute_path(int argc, VALUE *argv)
{
VALUE fname, dname;

if (argc == 1) {
return rb_file_absolute_path(argv[0], Qnil);
}

.atime(file_name) ⇒ Time

Returns the last access time for the named file as a Time object).

File.atime("testfile")   #=> Wed Apr 09 08:51:48 CDT 2003

Returns:


# File 'file.c'

static VALUE
rb_file_s_atime(VALUE klass, VALUE fname)
{
struct stat st;

if (rb_stat(fname, &st) < 0) {
FilePathValue(fname);
rb_sys_fail_path(fname);
}

.basename(file_name[, suffix]) ⇒ Object

Returns the last component of the filename given in file_name, which must be formed using forward slashes ("/'') regardless of the separator used on the local file system. If suffix is given and present at the end of file_name, it is removed.

File.basename("/home/gumby/work/ruby.rb")          #=> "ruby.rb"
File.basename("/home/gumby/work/ruby.rb", ".rb")   #=> "ruby"

# File 'file.c'

static VALUE
rb_file_s_basename(int argc, VALUE *argv)
{
VALUE fname, fext, basename;
const char *name, *p;
long f, n;

if (rb_scan_args(argc, argv, "11", &fname, &fext) == 2) {
rb_encoding *enc;
StringValue(fext);
if (!rb_enc_asciicompat(enc = rb_enc_get(fext))) {
    rb_raise(rb_eEncCompatError, "ascii incompatible character encodings: %s",
         rb_enc_name(enc));
}

.chmod(mode_int, file_name, ...) ⇒ Integer

Changes permission bits on the named file(s) to the bit pattern represented by mode_int. Actual effects are operating system dependent (see the beginning of this section). On Unix systems, see chmod(2) for details. Returns the number of files processed.

File.chmod(0644, "testfile", "out")   #=> 2

Returns:


# File 'file.c'

static VALUE
rb_file_s_chmod(int argc, VALUE *argv)
{
    VALUE vmode;
    VALUE rest;
    int mode;
    long n;

    rb_secure(2);
    rb_scan_args(argc, argv, "1*", &vmode, &rest);
    mode = NUM2INT(vmode);

    n = apply2files(chmod_internal, rest, &mode);
    return LONG2FIX(n);
}

.chown(owner_int, group_int, file_name, ...) ⇒ Integer

Changes the owner and group of the named file(s) to the given numeric owner and group id's. Only a process with superuser privileges may change the owner of a file. The current owner of a file may change the file's group to any group to which the owner belongs. A nil or -1 owner or group id is ignored. Returns the number of files processed.

File.chown(nil, 100, "testfile")

Returns:


# File 'file.c'

static VALUE
rb_file_s_chown(int argc, VALUE *argv)
{
VALUE o, g, rest;
struct chown_args arg;
long n;

rb_secure(2);
rb_scan_args(argc, argv, "2*", &o, &g, &rest);
if (NIL_P(o)) {
arg.owner = -1;
}

.ctime(file_name) ⇒ Time

Returns the change time for the named file (the time at which directory information about the file was changed, not the file itself).

Note that on Windows (NTFS), returns creation time (birth time).

File.ctime("testfile")   #=> Wed Apr 09 08:53:13 CDT 2003

Returns:


# File 'file.c'

static VALUE
rb_file_s_ctime(VALUE klass, VALUE fname)
{
struct stat st;

if (rb_stat(fname, &st) < 0) {
FilePathValue(fname);
rb_sys_fail_path(fname);
}

.delete(file_name, ...) ⇒ Integer .unlink(file_name, ...) ⇒ Integer

Deletes the named files, returning the number of names passed as arguments. Raises an exception on any error. See also Dir::rmdir.

Overloads:


# File 'file.c'

static VALUE
rb_file_s_unlink(VALUE klass, VALUE args)
{
    long n;

    rb_secure(2);
    n = apply2files(unlink_internal, args, 0);
    return LONG2FIX(n);
}

.dirname(file_name) ⇒ Object

Returns all components of the filename given in file_name except the last one. The filename must be formed using forward slashes ("/'') regardless of the separator used on the local file system.

File.dirname("/home/gumby/work/ruby.rb")   #=> "/home/gumby/work"

# File 'file.c'

static VALUE
rb_file_s_dirname(VALUE klass, VALUE fname)
{
    return rb_file_dirname(fname);
}

.expand_path(file_name[, dir_string]) ⇒ Object

Converts a pathname to an absolute pathname. Relative paths are referenced from the current working directory of the process unless dir_string is given, in which case it will be used as the starting point. The given pathname may start with a "~'', which expands to the process owner's home directory (the environment variable HOME must be set correctly). "~user'' expands to the named user's home directory.

File.expand_path("~oracle/bin")           #=> "/home/oracle/bin"
File.expand_path("../../bin", "/tmp/x")   #=> "/bin"

# File 'file.c'

VALUE
rb_file_s_expand_path(int argc, VALUE *argv)
{
VALUE fname, dname;

if (argc == 1) {
return rb_file_expand_path(argv[0], Qnil);
}

.extname(path) ⇒ String

Returns the extension (the portion of file name in path after the period).

File.extname("test.rb")         #=> ".rb"
File.extname("a/b/d/test.rb")   #=> ".rb"
File.extname("test")            #=> ""
File.extname(".profile")        #=> ""

Returns:


# File 'file.c'

static VALUE
rb_file_s_extname(VALUE klass, VALUE fname)
{
    const char *name, *e;
    long len;
    VALUE extname;

    FilePathStringValue(fname);
    name = StringValueCStr(fname);
    e = ruby_find_extname(name, &len);
    if (len <= 1)
    return rb_str_new(0, 0);
    extname = rb_str_new(e, len);   /* keep the dot, too! */
    rb_enc_copy(extname, fname);
    OBJ_INFECT(extname, fname);
    return extname;
}

.fnmatch(pattern, path, [flags]) ⇒ Boolean .fnmatch?(pattern, path, [flags]) ⇒ Boolean

Returns true if path matches against pattern The pattern is not a regular expression; instead it follows rules similar to shell filename globbing. It may contain the following metacharacters:

*

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 or files expansively.

?

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]).

<code></code>

Escapes the next metacharacter.

flags is a bitwise OR of the FNM_xxx parameters. The same glob pattern and flags are used by Dir::glob.

File.fnmatch('cat',       'cat')        #=> true  # match entire string
File.fnmatch('cat',       'category')   #=> false # only match partial string
File.fnmatch('c{at,ub}s', 'cats')       #=> false # { } isn't supported

File.fnmatch('c?t',     'cat')          #=> true  # '?' match only 1 character
File.fnmatch('c??t',    'cat')          #=> false # ditto
File.fnmatch('c*',      'cats')         #=> true  # '*' match 0 or more characters
File.fnmatch('c*t',     'c/a/b/t')      #=> true  # ditto
File.fnmatch('ca[a-z]', 'cat')          #=> true  # inclusive bracket expression
File.fnmatch('ca[^t]',  'cat')          #=> false # exclusive bracket expression ('^' or '!')

File.fnmatch('cat', 'CAT')                     #=> false # case sensitive
File.fnmatch('cat', 'CAT', File::FNM_CASEFOLD) #=> true  # case insensitive

File.fnmatch('?',   '/', File::FNM_PATHNAME)  #=> false # wildcard doesn't match '/' on FNM_PATHNAME
File.fnmatch('*',   '/', File::FNM_PATHNAME)  #=> false # ditto
File.fnmatch('[/]', '/', File::FNM_PATHNAME)  #=> false # ditto

File.fnmatch('\?',   '?')                       #=> true  # escaped wildcard becomes ordinary
File.fnmatch('\a',   'a')                       #=> true  # escaped ordinary remains ordinary
File.fnmatch('\a',   '\a', File::FNM_NOESCAPE)  #=> true  # FNM_NOESACPE makes '\' ordinary
File.fnmatch('[\?]', '?')                       #=> true  # can escape inside bracket expression

File.fnmatch('*',   '.profile')                      #=> false # wildcard doesn't match leading
File.fnmatch('*',   '.profile', File::FNM_DOTMATCH)  #=> true  # period by default.
File.fnmatch('.*',  '.profile')                      #=> true

rbfiles = '**' '/' '*.rb' # you don't have to do like this. just write in single string.
File.fnmatch(rbfiles, 'main.rb')                    #=> false
File.fnmatch(rbfiles, './main.rb')                  #=> false
File.fnmatch(rbfiles, 'lib/song.rb')                #=> true
File.fnmatch('**.rb', 'main.rb')                    #=> true
File.fnmatch('**.rb', './main.rb')                  #=> false
File.fnmatch('**.rb', 'lib/song.rb')                #=> true
File.fnmatch('*',           'dave/.profile')                      #=> true

pattern = '*' '/' '*'
File.fnmatch(pattern, 'dave/.profile', File::FNM_PATHNAME)  #=> false
File.fnmatch(pattern, 'dave/.profile', File::FNM_PATHNAME | File::FNM_DOTMATCH) #=> true

pattern = '**' '/' 'foo'
File.fnmatch(pattern, 'a/b/c/foo', File::FNM_PATHNAME)     #=> true
File.fnmatch(pattern, '/a/b/c/foo', File::FNM_PATHNAME)    #=> true
File.fnmatch(pattern, 'c:/a/b/c/foo', File::FNM_PATHNAME)  #=> true
File.fnmatch(pattern, 'a/.b/c/foo', File::FNM_PATHNAME)    #=> false
File.fnmatch(pattern, 'a/.b/c/foo', File::FNM_PATHNAME | File::FNM_DOTMATCH) #=> true

Overloads:

  • .fnmatch(pattern, path, [flags]) ⇒ Boolean

    Returns:

    • (Boolean)
  • .fnmatch?(pattern, path, [flags]) ⇒ Boolean

    Returns:

    • (Boolean)

# File 'dir.c'

static VALUE
file_s_fnmatch(int argc, VALUE *argv, VALUE obj)
{
    VALUE pattern, path;
    VALUE rflags;
    int flags;

    if (rb_scan_args(argc, argv, "21", &pattern, &path, &rflags) == 3)
    flags = NUM2INT(rflags);
    else
    flags = 0;

    StringValue(pattern);
    FilePathStringValue(path);

    if (fnmatch(RSTRING_PTR(pattern), rb_enc_get(pattern), RSTRING_PTR(path),
        flags) == 0)
    return Qtrue;

    return Qfalse;
}

.fnmatch(pattern, path, [flags]) ⇒ Boolean .fnmatch?(pattern, path, [flags]) ⇒ Boolean

Returns true if path matches against pattern The pattern is not a regular expression; instead it follows rules similar to shell filename globbing. It may contain the following metacharacters:

*

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 or files expansively.

?

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]).

<code></code>

Escapes the next metacharacter.

flags is a bitwise OR of the FNM_xxx parameters. The same glob pattern and flags are used by Dir::glob.

File.fnmatch('cat',       'cat')        #=> true  # match entire string
File.fnmatch('cat',       'category')   #=> false # only match partial string
File.fnmatch('c{at,ub}s', 'cats')       #=> false # { } isn't supported

File.fnmatch('c?t',     'cat')          #=> true  # '?' match only 1 character
File.fnmatch('c??t',    'cat')          #=> false # ditto
File.fnmatch('c*',      'cats')         #=> true  # '*' match 0 or more characters
File.fnmatch('c*t',     'c/a/b/t')      #=> true  # ditto
File.fnmatch('ca[a-z]', 'cat')          #=> true  # inclusive bracket expression
File.fnmatch('ca[^t]',  'cat')          #=> false # exclusive bracket expression ('^' or '!')

File.fnmatch('cat', 'CAT')                     #=> false # case sensitive
File.fnmatch('cat', 'CAT', File::FNM_CASEFOLD) #=> true  # case insensitive

File.fnmatch('?',   '/', File::FNM_PATHNAME)  #=> false # wildcard doesn't match '/' on FNM_PATHNAME
File.fnmatch('*',   '/', File::FNM_PATHNAME)  #=> false # ditto
File.fnmatch('[/]', '/', File::FNM_PATHNAME)  #=> false # ditto

File.fnmatch('\?',   '?')                       #=> true  # escaped wildcard becomes ordinary
File.fnmatch('\a',   'a')                       #=> true  # escaped ordinary remains ordinary
File.fnmatch('\a',   '\a', File::FNM_NOESCAPE)  #=> true  # FNM_NOESACPE makes '\' ordinary
File.fnmatch('[\?]', '?')                       #=> true  # can escape inside bracket expression

File.fnmatch('*',   '.profile')                      #=> false # wildcard doesn't match leading
File.fnmatch('*',   '.profile', File::FNM_DOTMATCH)  #=> true  # period by default.
File.fnmatch('.*',  '.profile')                      #=> true

rbfiles = '**' '/' '*.rb' # you don't have to do like this. just write in single string.
File.fnmatch(rbfiles, 'main.rb')                    #=> false
File.fnmatch(rbfiles, './main.rb')                  #=> false
File.fnmatch(rbfiles, 'lib/song.rb')                #=> true
File.fnmatch('**.rb', 'main.rb')                    #=> true
File.fnmatch('**.rb', './main.rb')                  #=> false
File.fnmatch('**.rb', 'lib/song.rb')                #=> true
File.fnmatch('*',           'dave/.profile')                      #=> true

pattern = '*' '/' '*'
File.fnmatch(pattern, 'dave/.profile', File::FNM_PATHNAME)  #=> false
File.fnmatch(pattern, 'dave/.profile', File::FNM_PATHNAME | File::FNM_DOTMATCH) #=> true

pattern = '**' '/' 'foo'
File.fnmatch(pattern, 'a/b/c/foo', File::FNM_PATHNAME)     #=> true
File.fnmatch(pattern, '/a/b/c/foo', File::FNM_PATHNAME)    #=> true
File.fnmatch(pattern, 'c:/a/b/c/foo', File::FNM_PATHNAME)  #=> true
File.fnmatch(pattern, 'a/.b/c/foo', File::FNM_PATHNAME)    #=> false
File.fnmatch(pattern, 'a/.b/c/foo', File::FNM_PATHNAME | File::FNM_DOTMATCH) #=> true

Overloads:

  • .fnmatch(pattern, path, [flags]) ⇒ Boolean

    Returns:

    • (Boolean)
  • .fnmatch?(pattern, path, [flags]) ⇒ Boolean

    Returns:

    • (Boolean)

# File 'dir.c'

static VALUE
file_s_fnmatch(int argc, VALUE *argv, VALUE obj)
{
    VALUE pattern, path;
    VALUE rflags;
    int flags;

    if (rb_scan_args(argc, argv, "21", &pattern, &path, &rflags) == 3)
    flags = NUM2INT(rflags);
    else
    flags = 0;

    StringValue(pattern);
    FilePathStringValue(path);

    if (fnmatch(RSTRING_PTR(pattern), rb_enc_get(pattern), RSTRING_PTR(path),
        flags) == 0)
    return Qtrue;

    return Qfalse;
}

.ftype(file_name) ⇒ String

Identifies the type of the named file; the return string is one of "file'', "directory'', "characterSpecial'', "blockSpecial'', "fifo'', "link'', "socket'', or "unknown''.

File.ftype("testfile")            #=> "file"
File.ftype("/dev/tty")            #=> "characterSpecial"
File.ftype("/tmp/.X11-unix/X0")   #=> "socket"

Returns:


# File 'file.c'

static VALUE
rb_file_s_ftype(VALUE klass, VALUE fname)
{
struct stat st;

rb_secure(2);
FilePathValue(fname);
fname = rb_str_encode_ospath(fname);
if (lstat(StringValueCStr(fname), &st) == -1) {
rb_sys_fail_path(fname);
}

.join(string, ...) ⇒ Object

Returns a new string formed by joining the strings using File::SEPARATOR.

File.join("usr", "mail", "gumby")   #=> "usr/mail/gumby"

# File 'file.c'

static VALUE
rb_file_s_join(VALUE klass, VALUE args)
{
    return rb_file_join(args, separator);
}

.lchmod(mode_int, file_name, ...) ⇒ Integer

Equivalent to File::chmod, but does not follow symbolic links (so it will change the permissions associated with the link, not the file referenced by the link). Often not available.

Returns:


# File 'file.c'

static VALUE
rb_file_s_lchmod(int argc, VALUE *argv)
{
    VALUE vmode;
    VALUE rest;
    long mode, n;

    rb_secure(2);
    rb_scan_args(argc, argv, "1*", &vmode, &rest);
    mode = NUM2INT(vmode);

    n = apply2files(lchmod_internal, rest, (void *)(long)mode);
    return LONG2FIX(n);
}

.lchown(owner_int, group_int, file_name, ..) ⇒ Integer

Equivalent to File::chown, but does not follow symbolic links (so it will change the owner associated with the link, not the file referenced by the link). Often not available. Returns number of files in the argument list.

Returns:


# File 'file.c'

static VALUE
rb_file_s_lchown(int argc, VALUE *argv)
{
VALUE o, g, rest;
struct chown_args arg;
long n;

rb_secure(2);
rb_scan_args(argc, argv, "2*", &o, &g, &rest);
if (NIL_P(o)) {
arg.owner = -1;
}

Creates a new name for an existing file using a hard link. Will not overwrite new_name if it already exists (raising a subclass of SystemCallError). Not available on all platforms.

File.link("testfile", ".testfile")   #=> 0
IO.readlines(".testfile")[0]         #=> "This is line one\n"

Returns:

  • (0)

# File 'file.c'

static VALUE
rb_file_s_link(VALUE klass, VALUE from, VALUE to)
{
rb_secure(2);
FilePathValue(from);
FilePathValue(to);
from = rb_str_encode_ospath(from);
to = rb_str_encode_ospath(to);

if (link(StringValueCStr(from), StringValueCStr(to)) < 0) {
sys_fail2(from, to);
}

.lstat(file_name) ⇒ Object

Same as File::stat, but does not follow the last symbolic link. Instead, reports on the link itself.

File.symlink("testfile", "link2test")   #=> 0
File.stat("testfile").size              #=> 66
File.lstat("link2test").size            #=> 8
File.stat("link2test").size             #=> 66

# File 'file.c'

static VALUE
rb_file_s_lstat(VALUE klass, VALUE fname)
{
#ifdef HAVE_LSTAT
struct stat st;

rb_secure(2);
FilePathValue(fname);
fname = rb_str_encode_ospath(fname);
if (lstat(StringValueCStr(fname), &st) == -1) {
rb_sys_fail_path(fname);
}

.mtime(file_name) ⇒ Time

Returns the modification time for the named file as a Time object.

File.mtime("testfile")   #=> Tue Apr 08 12:58:04 CDT 2003

Returns:


# File 'file.c'

static VALUE
rb_file_s_mtime(VALUE klass, VALUE fname)
{
struct stat st;

if (rb_stat(fname, &st) < 0) {
FilePathValue(fname);
rb_sys_fail_path(fname);
}

.open(filename, mode = "r"[, opt]) ⇒ File .open(filename[, mode [, perm]][, opt]) ⇒ File .open(filename, mode = "r"[, opt]) {|file| ... } ⇒ Object .open(filename[, mode [, perm]][, opt]) {|file| ... } ⇒ Object

With no associated block, File.open is a synonym for File.new. If the optional code block is given, it will be passed the opened file as an argument, and the File object will automatically be closed when the block terminates. In this instance, File.open returns the value of the block.

See IO.new for a list of values for the opt parameter.

Overloads:

  • .open(filename, mode = "r"[, opt]) ⇒ File

    Returns:

  • .open(filename[, mode [, perm]][, opt]) ⇒ File

    Returns:

  • .open(filename, mode = "r"[, opt]) {|file| ... } ⇒ Object

    Yields:

    • (file)

    Returns:

  • .open(filename[, mode [, perm]][, opt]) {|file| ... } ⇒ Object

    Yields:

    • (file)

    Returns:


# File 'io.c'

/*
 *  Document-method: IO::open
 *
 *  call-seq:
 *     IO.open(fd, mode_string="r" [, opt])               -> io
 *     IO.open(fd, mode_string="r" [, opt]) {|io| block } -> obj
 *
 *  With no associated block, <code>IO.open</code> is a synonym for IO.new. If
 *  the optional code block is given, it will be passed +io+ as an
 *  argument, and the IO object will automatically be closed when the block
 *  terminates. In this instance, IO.open returns the value of the block.
 *
 *  See IO.new for a description of values for the +opt+ parameter.
 *
 */

static VALUE
rb_io_s_open(int argc, VALUE *argv, VALUE klass)
{
VALUE io = rb_class_new_instance(argc, argv, klass);

if (rb_block_given_p()) {
return rb_ensure(rb_yield, io, io_close, io);
}

.path(path) ⇒ String

Returns the string representation of the path

File.path("/dev/null")          #=> "/dev/null"
File.path(Pathname.new("/tmp")) #=> "/tmp"

Returns:


# File 'file.c'

static VALUE
rb_file_s_path(VALUE klass, VALUE fname)
{
    return rb_get_path(fname);
}

Returns the name of the file referenced by the given link. Not available on all platforms.

File.symlink("testfile", "link2test")   #=> 0
File.readlink("link2test")              #=> "testfile"

# File 'file.c'

static VALUE
rb_file_s_readlink(VALUE klass, VALUE path)
{
char *buf;
int size = 100;
ssize_t rv;
VALUE v;

rb_secure(2);
FilePathValue(path);
path = rb_str_encode_ospath(path);
buf = xmalloc(size);
while ((rv = readlink(RSTRING_PTR(path), buf, size)) == size
#ifdef _AIX
    || (rv < 0 && errno == ERANGE) /* quirky behavior of GPFS */
#endif
) {
size *= 2;
buf = xrealloc(buf, size);
}

.realdirpath(pathname[, dir_string]) ⇒ Object

Returns the real (absolute) pathname of pathname in the actual filesystem.

The real pathname doesn't contain symlinks or useless dots.

If _dir_string_ is given, it is used as a base directory
for interpreting relative pathname instead of the current directory.

The last component of the real pathname can be nonexistent.

# File 'file.c'

static VALUE
rb_file_s_realdirpath(int argc, VALUE *argv, VALUE klass)
{
    VALUE path, basedir;
    rb_scan_args(argc, argv, "11", &path, &basedir);
    return rb_realpath_internal(basedir, path, 0);
}

.realpath(pathname[, dir_string]) ⇒ Object

Returns the real (absolute) pathname of pathname in the actual

filesystem not containing symlinks or useless dots.

If _dir_string_ is given, it is used as a base directory
for interpreting relative pathname instead of the current directory.

All components of the pathname must exist when this method is
called.

# File 'file.c'

static VALUE
rb_file_s_realpath(int argc, VALUE *argv, VALUE klass)
{
    VALUE path, basedir;
    rb_scan_args(argc, argv, "11", &path, &basedir);
    return rb_realpath_internal(basedir, path, 1);
}

.rename(old_name, new_name) ⇒ 0

Renames the given file to the new name. Raises a SystemCallError if the file cannot be renamed.

File.rename("afile", "afile.bak")   #=> 0

Returns:

  • (0)

# File 'file.c'

static VALUE
rb_file_s_rename(VALUE klass, VALUE from, VALUE to)
{
const char *src, *dst;
VALUE f, t;

rb_secure(2);
FilePathValue(from);
FilePathValue(to);
f = rb_str_encode_ospath(from);
t = rb_str_encode_ospath(to);
src = StringValueCStr(f);
dst = StringValueCStr(t);
#if defined __CYGWIN__
errno = 0;
#endif
if (rename(src, dst) < 0) {
#if defined DOSISH
switch (errno) {
  case EEXIST:
#if defined (__EMX__)
  case EACCES:
#endif
    if (chmod(dst, 0666) == 0 &&
    unlink(dst) == 0 &&
    rename(src, dst) == 0)
    return INT2FIX(0);
}

.split(file_name) ⇒ Array

Splits the given string into a directory and a file component and returns them in a two-element array. See also File::dirname and File::basename.

File.split("/home/gumby/.profile")   #=> ["/home/gumby", ".profile"]

Returns:


# File 'file.c'

static VALUE
rb_file_s_split(VALUE klass, VALUE path)
{
    FilePathStringValue(path);      /* get rid of converting twice */
    return rb_assoc_new(rb_file_s_dirname(Qnil, path), rb_file_s_basename(1,&path));
}

.stat(file_name) ⇒ Object

Returns a File::Stat object for the named file (see File::Stat).

File.stat("testfile").mtime   #=> Tue Apr 08 12:58:04 CDT 2003

# File 'file.c'

static VALUE
rb_file_s_stat(VALUE klass, VALUE fname)
{
struct stat st;

rb_secure(4);
FilePathValue(fname);
if (rb_stat(fname, &st) < 0) {
rb_sys_fail_path(fname);
}

Creates a symbolic link called new_name for the existing file old_name. Raises a NotImplemented exception on platforms that do not support symbolic links.

File.symlink("testfile", "link2test")   #=> 0

Returns:

  • (0)

# File 'file.c'

static VALUE
rb_file_s_symlink(VALUE klass, VALUE from, VALUE to)
{
rb_secure(2);
FilePathValue(from);
FilePathValue(to);
from = rb_str_encode_ospath(from);
to = rb_str_encode_ospath(to);

if (symlink(StringValueCStr(from), StringValueCStr(to)) < 0) {
sys_fail2(from, to);
}

.truncate(file_name, integer) ⇒ 0

Truncates the file file_name to be at most integer bytes long. Not available on all platforms.

f = File.new("out", "w")
f.write("1234567890")     #=> 10
f.close                   #=> nil
File.truncate("out", 5)   #=> 0
File.size("out")          #=> 5

Returns:

  • (0)

# File 'file.c'

static VALUE
rb_file_s_truncate(VALUE klass, VALUE path, VALUE len)
{
off_t pos;

rb_secure(2);
pos = NUM2OFFT(len);
FilePathValue(path);
path = rb_str_encode_ospath(path);
#ifdef HAVE_TRUNCATE
if (truncate(StringValueCStr(path), pos) < 0)
rb_sys_fail_path(path);
#else /* defined(HAVE_CHSIZE) */
{
int tmpfd;

if ((tmpfd = open(StringValueCStr(path), 0)) < 0) {
    rb_sys_fail_path(path);
}

.umaskInteger .umask(integer) ⇒ Integer

Returns the current umask value for this process. If the optional argument is given, set the umask to that value and return the previous value. Umask values are subtracted from the default permissions, so a umask of 0222 would make a file read-only for everyone.

File.umask(0006)   #=> 18
File.umask         #=> 6

Overloads:


# File 'file.c'

static VALUE
rb_file_s_umask(int argc, VALUE *argv)
{
int omask = 0;

rb_secure(2);
if (argc == 0) {
omask = umask(0);
umask(omask);
}

Deletes the named files, returning the number of names passed as arguments. Raises an exception on any error. See also Dir::rmdir.

Overloads:


# File 'file.c'

static VALUE
rb_file_s_unlink(VALUE klass, VALUE args)
{
    long n;

    rb_secure(2);
    n = apply2files(unlink_internal, args, 0);
    return LONG2FIX(n);
}

.utime(atime, mtime, file_name, ...) ⇒ Integer

Sets the access and modification times of each named file to the first two arguments. Returns the number of file names in the argument list.

Returns:


# File 'file.c'

static VALUE
rb_file_s_utime(int argc, VALUE *argv)
{
VALUE rest;
struct utime_args args;
struct timespec tss[2], *tsp = NULL;
long n;

rb_secure(2);
rb_scan_args(argc, argv, "2*", &args.atime, &args.mtime, &rest);

if (!NIL_P(args.atime) || !NIL_P(args.mtime)) {
tsp = tss;
tsp[0] = rb_time_timespec(args.atime);
tsp[1] = rb_time_timespec(args.mtime);
}

Instance Method Details

#atimeTime

Returns the last access time (a Time object)

for <i>file</i>, or epoch if <i>file</i> has not been accessed.

  File.new("testfile").atime   #=> Wed Dec 31 18:00:00 CST 1969

Returns:


# File 'file.c'

static VALUE
rb_file_atime(VALUE obj)
{
rb_io_t *fptr;
struct stat st;

GetOpenFile(obj, fptr);
if (fstat(fptr->fd, &st) == -1) {
rb_sys_fail_path(fptr->pathv);
}

#chmod(mode_int) ⇒ 0

Changes permission bits on file to the bit pattern represented by mode_int. Actual effects are platform dependent; on Unix systems, see chmod(2) for details. Follows symbolic links. Also see File#lchmod.

f = File.new("out", "w");
f.chmod(0644)   #=> 0

Returns:

  • (0)

# File 'file.c'

static VALUE
rb_file_chmod(VALUE obj, VALUE vmode)
{
    rb_io_t *fptr;
    int mode;
#ifndef HAVE_FCHMOD
    VALUE path;
#endif

    rb_secure(2);
    mode = NUM2INT(vmode);

    GetOpenFile(obj, fptr);
#ifdef HAVE_FCHMOD
    if (fchmod(fptr->fd, mode) == -1)
    rb_sys_fail_path(fptr->pathv);
#else
    if (NIL_P(fptr->pathv)) return Qnil;
    path = rb_str_encode_ospath(fptr->pathv);
    if (chmod(RSTRING_PTR(path), mode) == -1)
    rb_sys_fail_path(fptr->pathv);
#endif

    return INT2FIX(0);
}

#chown(owner_int, group_int) ⇒ 0

Changes the owner and group of file to the given numeric owner and group id's. Only a process with superuser privileges may change the owner of a file. The current owner of a file may change the file's group to any group to which the owner belongs. A nil or -1 owner or group id is ignored. Follows symbolic links. See also File#lchown.

File.new("testfile").chown(502, 1000)

Returns:

  • (0)

# File 'file.c'

static VALUE
rb_file_chown(VALUE obj, VALUE owner, VALUE group)
{
    rb_io_t *fptr;
    int o, g;
#ifndef HAVE_FCHOWN
    VALUE path;
#endif

    rb_secure(2);
    o = NIL_P(owner) ? -1 : NUM2INT(owner);
    g = NIL_P(group) ? -1 : NUM2INT(group);
    GetOpenFile(obj, fptr);
#ifndef HAVE_FCHOWN
    if (NIL_P(fptr->pathv)) return Qnil;
    path = rb_str_encode_ospath(fptr->pathv);
    if (chown(RSTRING_PTR(path), o, g) == -1)
    rb_sys_fail_path(fptr->pathv);
#else
    if (fchown(fptr->fd, o, g) == -1)
    rb_sys_fail_path(fptr->pathv);
#endif

    return INT2FIX(0);
}

#ctimeTime

Returns the change time for file (that is, the time directory information about the file was changed, not the file itself).

Note that on Windows (NTFS), returns creation time (birth time).

File.new("testfile").ctime   #=> Wed Apr 09 08:53:14 CDT 2003

Returns:


# File 'file.c'

static VALUE
rb_file_ctime(VALUE obj)
{
rb_io_t *fptr;
struct stat st;

GetOpenFile(obj, fptr);
if (fstat(fptr->fd, &st) == -1) {
rb_sys_fail_path(fptr->pathv);
}

#flockObject

Locks or unlocks a file according to locking_constant (a logical or of the values in the table below). Returns false if File::LOCK_NB is specified and the operation would otherwise have blocked. Not available on all platforms.

Locking constants (in class File):

LOCK_EX   | Exclusive lock. Only one process may hold an
          | exclusive lock for a given file at a time.
----------+------------------------------------------------
LOCK_NB   | Don't block when locking. May be combined
          | with other lock options using logical or.
----------+------------------------------------------------
LOCK_SH   | Shared lock. Multiple processes may each hold a
          | shared lock for a given file at the same time.
----------+------------------------------------------------
LOCK_UN   | Unlock.

Example:

# update a counter using write lock
# don't use "w" because it truncates the file before lock.
File.open("counter", File::RDWR|File::CREAT, 0644) {|f|
  f.flock(File::LOCK_EX)
  value = f.read.to_i + 1
  f.rewind
  f.write("#{value}\n")
  f.flush
  f.truncate(f.pos)
}

# read the counter using read lock
File.open("counter", "r") {|f|
  f.flock(File::LOCK_SH)
  p f.read
}

# File 'file.c'

static VALUE
rb_file_flock(VALUE obj, VALUE operation)
{
rb_io_t *fptr;
int op[2], op1;

rb_secure(2);
op[1] = op1 = NUM2INT(operation);
GetOpenFile(obj, fptr);
op[0] = fptr->fd;

if (fptr->mode & FMODE_WRITABLE) {
rb_io_flush(obj);
}

#lstatObject

Same as IO#stat, but does not follow the last symbolic link. Instead, reports on the link itself.

File.symlink("testfile", "link2test")   #=> 0
File.stat("testfile").size              #=> 66
f = File.new("link2test")
f.lstat.size                            #=> 8
f.stat.size                             #=> 66

# File 'file.c'

static VALUE
rb_file_lstat(VALUE obj)
{
#ifdef HAVE_LSTAT
rb_io_t *fptr;
struct stat st;
VALUE path;

rb_secure(2);
GetOpenFile(obj, fptr);
if (NIL_P(fptr->pathv)) return Qnil;
path = rb_str_encode_ospath(fptr->pathv);
if (lstat(RSTRING_PTR(path), &st) == -1) {
rb_sys_fail_path(fptr->pathv);
}

#mtimeTime

Returns the modification time for file.

File.new("testfile").mtime   #=> Wed Apr 09 08:53:14 CDT 2003

Returns:


# File 'file.c'

static VALUE
rb_file_mtime(VALUE obj)
{
rb_io_t *fptr;
struct stat st;

GetOpenFile(obj, fptr);
if (fstat(fptr->fd, &st) == -1) {
rb_sys_fail_path(fptr->pathv);
}

#pathObject

Returns the pathname used to create file as a string. Does not normalize the name.

File.new("testfile").path               #=> "testfile"
File.new("/tmp/../tmp/xxx", "w").path   #=> "/tmp/../tmp/xxx"

# File 'file.c'

static VALUE
rb_file_path(VALUE obj)
{
    rb_io_t *fptr;

    fptr = RFILE(rb_io_taint_check(obj))->fptr;
    rb_io_check_initialized(fptr);
    if (NIL_P(fptr->pathv)) return Qnil;
    return rb_obj_taint(rb_str_dup(fptr->pathv));
}

#sizeInteger

Returns the size of file in bytes.

File.new("testfile").size   #=> 66

Returns:


# File 'file.c'

static VALUE
rb_file_size(VALUE obj)
{
rb_io_t *fptr;
struct stat st;

GetOpenFile(obj, fptr);
if (fptr->mode & FMODE_WRITABLE) {
rb_io_flush(obj);
}

#pathObject

Returns the pathname used to create file as a string. Does not normalize the name.

File.new("testfile").path               #=> "testfile"
File.new("/tmp/../tmp/xxx", "w").path   #=> "/tmp/../tmp/xxx"

# File 'file.c'

static VALUE
rb_file_path(VALUE obj)
{
    rb_io_t *fptr;

    fptr = RFILE(rb_io_taint_check(obj))->fptr;
    rb_io_check_initialized(fptr);
    if (NIL_P(fptr->pathv)) return Qnil;
    return rb_obj_taint(rb_str_dup(fptr->pathv));
}

#truncate(integer) ⇒ 0

Truncates file to at most integer bytes. The file must be opened for writing. Not available on all platforms.

f = File.new("out", "w")
f.syswrite("1234567890")   #=> 10
f.truncate(5)              #=> 0
f.close()                  #=> nil
File.size("out")           #=> 5

Returns:

  • (0)

# File 'file.c'

static VALUE
rb_file_truncate(VALUE obj, VALUE len)
{
rb_io_t *fptr;
off_t pos;

rb_secure(2);
pos = NUM2OFFT(len);
GetOpenFile(obj, fptr);
if (!(fptr->mode & FMODE_WRITABLE)) {
rb_raise(rb_eIOError, "not opened for writing");
}