class File

static VALUE
s_absolute_path(int c, const VALUE * v, VALUE _)
{
    return rb_file_s_absolute_path(c, v);
}

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"

static VALUE
s_absolute_path_p(VALUE klass, VALUE fname)
{
    VALUE path = rb_get_path(fname);

    if (!rb_is_absolute_path(RSTRING_PTR(path))) return Qfalse;
    return Qtrue;
}

Returns true if file_name is an absolute path, and false otherwise.

File.absolute_path?("c:/foo")     #=> false (on Linux), true (on Windows)

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

    if (rb_stat(fname, &st) < 0) {
        int e = errno;
        FilePathValue(fname);
        rb_syserr_fail_path(e, fname);
    }
    return stat_atime(&st);
}

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

file_name can be an IO object.

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

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

    fext = Qnil;
    if (rb_check_arity(argc, 1, 2) == 2) {
        fext = argv[1];
        StringValue(fext);
        enc = check_path_encoding(fext);
    }
    fname = argv[0];
    FilePathStringValue(fname);
    if (NIL_P(fext) || !(enc = rb_enc_compatible(fname, fext))) {
        enc = rb_enc_get(fname);
        fext = Qnil;
    }
    if ((n = RSTRING_LEN(fname)) == 0 || !*(name = RSTRING_PTR(fname)))
        return rb_str_new_shared(fname);

    p = ruby_enc_find_basename(name, &f, &n, enc);
    if (n >= 0) {
        if (NIL_P(fext)) {
            f = n;
        }
        else {
            const char *fp;
            fp = StringValueCStr(fext);
            if (!(f = rmext(p, f, n, fp, RSTRING_LEN(fext), enc))) {
                f = n;
            }
            RB_GC_GUARD(fext);
        }
        if (f == RSTRING_LEN(fname)) return rb_str_new_shared(fname);
    }

    basename = rb_str_new(p, f);
    rb_enc_copy(basename, fname);
    return basename;
}

Returns the last component of the filename given in file_name (after first stripping trailing separators), which can be formed using both File::SEPARATOR and File::ALT_SEPARATOR as the separator when File::ALT_SEPARATOR is not nil. If suffix is given and present at the end of file_name, it is removed. If suffix is “.*”, any extension will be removed.

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

static VALUE
rb_file_blockdev_p(VALUE obj, VALUE fname)
{
#ifndef S_ISBLK
#   ifdef S_IFBLK
#       define S_ISBLK(m) (((m) & S_IFMT) == S_IFBLK)
#   else
#       define S_ISBLK(m) (0)  /* anytime false */
#   endif
#endif

#ifdef S_ISBLK
    struct stat st;

    if (rb_stat(fname, &st) < 0) return Qfalse;
    if (S_ISBLK(st.st_mode)) return Qtrue;

#endif
    return Qfalse;
}

Returns true if the named file is a block device.

file_name can be an IO object.

static VALUE
rb_file_chardev_p(VALUE obj, VALUE fname)
{
#ifndef S_ISCHR
#   define S_ISCHR(m) (((m) & S_IFMT) == S_IFCHR)
#endif

    struct stat st;

    if (rb_stat(fname, &st) < 0) return Qfalse;
    if (S_ISCHR(st.st_mode)) return Qtrue;

    return Qfalse;
}

Returns true if the named file is a character device.

file_name can be an IO object.

static VALUE
rb_file_s_chmod(int argc, VALUE *argv, VALUE _)
{
    mode_t mode;

    apply2args(1);
    mode = NUM2MODET(*argv++);

    return apply2files(chmod_internal, argc, argv, &mode);
}

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

static VALUE
rb_file_s_chown(int argc, VALUE *argv, VALUE _)
{
    struct chown_args arg;

    apply2args(2);
    arg.owner = to_uid(*argv++);
    arg.group = to_gid(*argv++);

    return apply2files(chown_internal, argc, argv, &arg);
}

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")

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

    if (rb_stat(fname, &st) < 0) {
        int e = errno;
        FilePathValue(fname);
        rb_syserr_fail_path(e, fname);
    }
    return stat_ctime(&st);
}

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

file_name can be an IO object.

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

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

static VALUE
rb_file_s_unlink(int argc, VALUE *argv, VALUE klass)
{
    return apply2files(unlink_internal, argc, argv, 0);
}

Deletes the named files, returning the number of names passed as arguments. Raises an exception on any error. Since the underlying implementation relies on the unlink(2) system call, the type of exception raised depends on its error type (see linux.die.net/man/2/unlink) and has the form of e.g. Errno::ENOENT.

See also Dir::rmdir.

VALUE
rb_file_directory_p(VALUE obj, VALUE fname)
{
#ifndef S_ISDIR
#   define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
#endif

    struct stat st;

    if (rb_stat(fname, &st) < 0) return Qfalse;
    if (S_ISDIR(st.st_mode)) return Qtrue;
    return Qfalse;
}

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

file_name can be an IO object.

File.directory?(".")

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

Returns all components of the filename given in file_name except the last one (after first stripping trailing separators). The filename can be formed using both File::SEPARATOR and File::ALT_SEPARATOR as the separator when File::ALT_SEPARATOR is not nil.

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

static VALUE
rb_file_zero_p(VALUE obj, VALUE fname)
{
    struct stat st;

    if (rb_stat(fname, &st) < 0) return Qfalse;
    if (st.st_size == 0) return Qtrue;
    return Qfalse;
}

Returns true if the named file exists and has a zero size.

file_name can be an IO object.

static VALUE
rb_file_executable_p(VALUE obj, VALUE fname)
{
    if (rb_eaccess(fname, X_OK) < 0) return Qfalse;
    return Qtrue;
}

Returns true if the named file is executable by the effective user and group id of this process. See eaccess(3).

Windows does not support execute permissions separately from read permissions. On Windows, a file is only considered executable if it ends in .bat, .cmd, .com, or .exe.

Note that some OS-level security features may cause this to return true even though the file is not executable by the effective user/group.

static VALUE
rb_file_executable_real_p(VALUE obj, VALUE fname)
{
    if (rb_access(fname, X_OK) < 0) return Qfalse;
    return Qtrue;
}

Returns true if the named file is executable by the real user and group id of this process. See access(3).

Windows does not support execute permissions separately from read permissions. On Windows, a file is only considered executable if it ends in .bat, .cmd, .com, or .exe.

Note that some OS-level security features may cause this to return true even though the file is not executable by the real user/group.

static VALUE
rb_file_exist_p(VALUE obj, VALUE fname)
{
    struct stat st;

    if (rb_stat(fname, &st) < 0) return Qfalse;
    return Qtrue;
}

Return true if the named file exists.

file_name can be an IO object.

“file exists” means that stat() or fstat() system call is successful.

static VALUE
s_expand_path(int c, const VALUE * v, VALUE _)
{
    return rb_file_s_expand_path(c, v);
}

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"

A simple example of using dir_string is as follows.

File.expand_path("ruby", "/usr/bin")      #=> "/usr/bin/ruby"

A more complex example which also resolves parent directory is as follows. Suppose we are in bin/mygem and want the absolute path of lib/mygem.rb.

File.expand_path("../../lib/mygem.rb", __FILE__)
#=> ".../path/to/project/lib/mygem.rb"

So first it resolves the parent of __FILE__, that is bin/, then go to the parent, the root of the project and appends lib/mygem.rb.

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

    FilePathStringValue(fname);
    name = StringValueCStr(fname);
    len = RSTRING_LEN(fname);
    e = ruby_enc_find_extname(name, &len, rb_enc_get(fname));
    if (len < 1)
        return rb_str_new(0, 0);
    extname = rb_str_subseq(fname, e - name, len); /* keep the dot, too! */
    return extname;
}

Returns the extension (the portion of file name in path starting from the last period).

If path is a dotfile, or starts with a period, then the starting dot is not dealt with the start of the extension.

An empty string will also be returned when the period is the last character in path.

On Windows, trailing dots are truncated.

File.extname("test.rb")         #=> ".rb"
File.extname("a/b/d/test.rb")   #=> ".rb"
File.extname(".a/b/d/test.rb")  #=> ".rb"
File.extname("foo.")            #=> "" on Windows
File.extname("foo.")            #=> "." on non-Windows
File.extname("test")            #=> ""
File.extname(".profile")        #=> ""
File.extname(".profile.sh")     #=> ".sh"

static VALUE
rb_file_file_p(VALUE obj, VALUE fname)
{
    struct stat st;

    if (rb_stat(fname, &st) < 0) return Qfalse;
    if (S_ISREG(st.st_mode)) return Qtrue;
    return Qfalse;
}

Returns true if the named file exists and is a regular file.

file can be an IO object.

If the file argument is a symbolic link, it will resolve the symbolic link and use the file referenced by the link.

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;

    StringValueCStr(pattern);
    FilePathStringValue(path);

    if (flags & FNM_EXTGLOB) {
        struct brace_args args;

        args.value = path;
        args.flags = flags;
        if (ruby_brace_expand(RSTRING_PTR(pattern), flags, fnmatch_brace,
                              (VALUE)&args, rb_enc_get(pattern), pattern) > 0)
            return Qtrue;
    }
    else {
        rb_encoding *enc = rb_enc_compatible(pattern, path);
        if (!enc) return Qfalse;
        if (fnmatch(RSTRING_PTR(pattern), enc, RSTRING_PTR(path), flags) == 0)
            return Qtrue;
    }
    RB_GC_GUARD(pattern);

    return Qfalse;
}

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. Equivalent to / .* /x in regexp.

*

Matches all files regular files

c*

Matches all files beginning with c

*c

Matches all files ending with c

*c*

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

To match hidden files (that start with a . set the File::FNM_DOTMATCH flag.

**

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]).

\

Escapes the next metacharacter.

{a,b}

Matches pattern a and pattern b if File::FNM_EXTGLOB flag is enabled. Behaves like a Regexp union ((?:a|b)).

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

Examples:

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 by default
File.fnmatch('c{at,ub}s', 'cats', File::FNM_EXTGLOB) #=> true  # { } is supported on FNM_EXTGLOB

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('cat', 'CAT', File::FNM_SYSCASE)  #=> true or false # depends on the system default

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_NOESCAPE 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

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;

    StringValueCStr(pattern);
    FilePathStringValue(path);

    if (flags & FNM_EXTGLOB) {
        struct brace_args args;

        args.value = path;
        args.flags = flags;
        if (ruby_brace_expand(RSTRING_PTR(pattern), flags, fnmatch_brace,
                              (VALUE)&args, rb_enc_get(pattern), pattern) > 0)
            return Qtrue;
    }
    else {
        rb_encoding *enc = rb_enc_compatible(pattern, path);
        if (!enc) return Qfalse;
        if (fnmatch(RSTRING_PTR(pattern), enc, RSTRING_PTR(path), flags) == 0)
            return Qtrue;
    }
    RB_GC_GUARD(pattern);

    return Qfalse;
}

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. Equivalent to / .* /x in regexp.

*

Matches all files regular files

c*

Matches all files beginning with c

*c

Matches all files ending with c

*c*

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

To match hidden files (that start with a . set the File::FNM_DOTMATCH flag.

**

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]).

\

Escapes the next metacharacter.

{a,b}

Matches pattern a and pattern b if File::FNM_EXTGLOB flag is enabled. Behaves like a Regexp union ((?:a|b)).

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

Examples:

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 by default
File.fnmatch('c{at,ub}s', 'cats', File::FNM_EXTGLOB) #=> true  # { } is supported on FNM_EXTGLOB

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('cat', 'CAT', File::FNM_SYSCASE)  #=> true or false # depends on the system default

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_NOESCAPE 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

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

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

    return rb_file_ftype(&st);
}

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"

static VALUE
rb_file_grpowned_p(VALUE obj, VALUE fname)
{
#ifndef _WIN32
    struct stat st;

    if (rb_stat(fname, &st) < 0) return Qfalse;
    if (rb_group_member(st.st_gid)) return Qtrue;
#endif
    return Qfalse;
}

Returns true if the named file exists and the effective group id of the calling process is the owner of the file. Returns false on Windows.

file_name can be an IO object.

static VALUE
rb_file_identical_p(VALUE obj, VALUE fname1, VALUE fname2)
{
#ifndef _WIN32
    struct stat st1, st2;

    if (rb_stat(fname1, &st1) < 0) return Qfalse;
    if (rb_stat(fname2, &st2) < 0) return Qfalse;
    if (st1.st_dev != st2.st_dev) return Qfalse;
    if (st1.st_ino != st2.st_ino) return Qfalse;
    return Qtrue;
#else
    extern VALUE rb_w32_file_identical_p(VALUE, VALUE);
    return rb_w32_file_identical_p(fname1, fname2);
#endif
}

Returns true if the named files are identical.

file_1 and file_2 can be an IO object.

open("a", "w") {}
p File.identical?("a", "a")      #=> true
p File.identical?("a", "./a")    #=> true
File.link("a", "b")
p File.identical?("a", "b")      #=> true
File.symlink("a", "c")
p File.identical?("a", "c")      #=> true
open("d", "w") {}
p File.identical?("a", "d")      #=> false

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

Returns a new string formed by joining the strings using "/".

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

static VALUE
rb_file_s_lchmod(int argc, VALUE *argv, VALUE _)
{
    mode_t mode;

    apply2args(1);
    mode = NUM2MODET(*argv++);

    return apply2files(lchmod_internal, argc, argv, &mode);
}

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.

static VALUE
rb_file_s_lchown(int argc, VALUE *argv, VALUE _)
{
    struct chown_args arg;

    apply2args(2);
    arg.owner = to_uid(*argv++);
    arg.group = to_gid(*argv++);

    return apply2files(lchown_internal, argc, argv, &arg);
}

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.

static VALUE
rb_file_s_link(VALUE klass, VALUE from, VALUE to)
{
    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);
    }
    return INT2FIX(0);
}

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"

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

    FilePathValue(fname);
    fname = rb_str_encode_ospath(fname);
    if (lstat_without_gvl(StringValueCStr(fname), &st) == -1) {
        rb_sys_fail_path(fname);
    }
    return rb_stat_new(&st);
#else
    return rb_file_s_stat(klass, fname);
#endif
}

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

static VALUE
rb_file_s_lutime(int argc, VALUE *argv, VALUE _)
{
    return utime_internal_i(argc, argv, TRUE);
}

Sets the access and modification times of each named file to the first two arguments. If a file is a symlink, this method acts upon the link itself as opposed to its referent; for the inverse behavior, see File.utime. Returns the number of file names in the argument list.

static VALUE
rb_file_s_mkfifo(int argc, VALUE *argv, VALUE _)
{
    VALUE path;
    struct mkfifo_arg ma;

    ma.mode = 0666;
    rb_check_arity(argc, 1, 2);
    if (argc > 1) {
        ma.mode = NUM2MODET(argv[1]);
    }
    path = argv[0];
    FilePathValue(path);
    path = rb_str_encode_ospath(path);
    ma.path = RSTRING_PTR(path);
    if (rb_thread_call_without_gvl(nogvl_mkfifo, &ma, RUBY_UBF_IO, 0)) {
        rb_sys_fail_path(path);
    }
    return INT2FIX(0);
}

Creates a FIFO special file with name file_name. mode specifies the FIFO's permissions. It is modified by the process's umask in the usual way: the permissions of the created file are (mode & ~umask).

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

    if (rb_stat(fname, &st) < 0) {
        int e = errno;
        FilePathValue(fname);
        rb_syserr_fail_path(e, fname);
    }
    return stat_mtime(&st);
}

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

file_name can be an IO object.

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

static VALUE
rb_file_initialize(int argc, VALUE *argv, VALUE io)
{
    if (RFILE(io)->fptr) {
        rb_raise(rb_eRuntimeError, "reinitializing File");
    }
    if (0 < argc && argc < 3) {
        VALUE fd = rb_check_to_int(argv[0]);

        if (!NIL_P(fd)) {
            argv[0] = fd;
            return rb_io_initialize(argc, argv, io);
        }
    }
    rb_open_file(argc, argv, io);

    return io;
}

Opens the file named by filename according to the given mode and returns a new File object.

See IO.new for a description of mode and opt.

If a file is being created, permission bits may be given in perm. These mode and permission bits are platform dependent; on Unix systems, see open(2) and chmod(2) man pages for details.

The new File object is buffered mode (or non-sync mode), unless filename is a tty. See IO#flush, IO#fsync, IO#fdatasync, and IO#sync= about sync mode.

Examples

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

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

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

    return io;
}

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. The value of the block will be returned from File.open.

If a file is being created, its initial permissions may be set using the perm parameter. See File.new for further discussion.

See IO.new for a description of the mode and opt parameters.

static VALUE
rb_file_owned_p(VALUE obj, VALUE fname)
{
    struct stat st;

    if (rb_stat(fname, &st) < 0) return Qfalse;
    if (st.st_uid == geteuid()) return Qtrue;
    return Qfalse;
}

Returns true if the named file exists and the effective used id of the calling process is the owner of the file.

file_name can be an IO object.

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

Returns the string representation of the path

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

static VALUE
rb_file_pipe_p(VALUE obj, VALUE fname)
{
#ifdef S_IFIFO
#  ifndef S_ISFIFO
#    define S_ISFIFO(m) (((m) & S_IFMT) == S_IFIFO)
#  endif

    struct stat st;

    if (rb_stat(fname, &st) < 0) return Qfalse;
    if (S_ISFIFO(st.st_mode)) return Qtrue;

#endif
    return Qfalse;
}

Returns true if the named file is a pipe.

file_name can be an IO object.

static VALUE
rb_file_readable_p(VALUE obj, VALUE fname)
{
    if (rb_eaccess(fname, R_OK) < 0) return Qfalse;
    return Qtrue;
}

Returns true if the named file is readable by the effective user and group id of this process. See eaccess(3).

Note that some OS-level security features may cause this to return true even though the file is not readable by the effective user/group.

static VALUE
rb_file_readable_real_p(VALUE obj, VALUE fname)
{
    if (rb_access(fname, R_OK) < 0) return Qfalse;
    return Qtrue;
}

Returns true if the named file is readable by the real user and group id of this process. See access(3).

Note that some OS-level security features may cause this to return true even though the file is not readable by the real user/group.

static VALUE
rb_file_s_readlink(VALUE klass, VALUE path)
{
    return rb_readlink(path, rb_filesystem_encoding());
}

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"

static VALUE
rb_file_s_realdirpath(int argc, VALUE *argv, VALUE klass)
{
    VALUE basedir = (rb_check_arity(argc, 1, 2) > 1) ? argv[1] : Qnil;
    VALUE path = argv[0];
    FilePathValue(path);
    return rb_realpath_internal(basedir, path, 0);
}

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.

static VALUE
rb_file_s_realpath(int argc, VALUE *argv, VALUE klass)
{
    VALUE basedir = (rb_check_arity(argc, 1, 2) > 1) ? argv[1] : Qnil;
    VALUE path = argv[0];
    FilePathValue(path);
    return rb_realpath_internal(basedir, path, 1);
}

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.

static VALUE
rb_file_s_rename(VALUE klass, VALUE from, VALUE to)
{
    struct rename_args ra;
    VALUE f, t;

    FilePathValue(from);
    FilePathValue(to);
    f = rb_str_encode_ospath(from);
    t = rb_str_encode_ospath(to);
    ra.src = StringValueCStr(f);
    ra.dst = StringValueCStr(t);
#if defined __CYGWIN__
    errno = 0;
#endif
    if ((int)(VALUE)rb_thread_call_without_gvl(no_gvl_rename, &ra,
                                         RUBY_UBF_IO, 0) < 0) {
        int e = errno;
#if defined DOSISH
        switch (e) {
          case EEXIST:
            if (chmod(ra.dst, 0666) == 0 &&
                unlink(ra.dst) == 0 &&
                rename(ra.src, ra.dst) == 0)
                return INT2FIX(0);
        }
#endif
        syserr_fail2(e, from, to);
    }

    return INT2FIX(0);
}

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

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

static VALUE
rb_file_sgid_p(VALUE obj, VALUE fname)
{
#ifdef S_ISGID
    return check3rdbyte(fname, S_ISGID);
#else
    return Qfalse;
#endif
}

Returns true if the named file has the setgid bit set.

file_name can be an IO object.

static VALUE
rb_file_suid_p(VALUE obj, VALUE fname)
{
#ifdef S_ISUID
    return check3rdbyte(fname, S_ISUID);
#else
    return Qfalse;
#endif
}

Returns true if the named file has the setuid bit set.

file_name can be an IO object.

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

    if (rb_stat(fname, &st) < 0) {
        int e = errno;
        FilePathValue(fname);
        rb_syserr_fail_path(e, fname);
    }
    return OFFT2NUM(st.st_size);
}

Returns the size of file_name.

file_name can be an IO object.

static VALUE
rb_file_size_p(VALUE obj, VALUE fname)
{
    struct stat st;

    if (rb_stat(fname, &st) < 0) return Qnil;
    if (st.st_size == 0) return Qnil;
    return OFFT2NUM(st.st_size);
}

Returns nil if file_name doesn't exist or has zero size, the size of the file otherwise.

file_name can be an IO object.

static VALUE
rb_file_socket_p(VALUE obj, VALUE fname)
{
#ifndef S_ISSOCK
#  ifdef _S_ISSOCK
#    define S_ISSOCK(m) _S_ISSOCK(m)
#  else
#    ifdef _S_IFSOCK
#      define S_ISSOCK(m) (((m) & S_IFMT) == _S_IFSOCK)
#    else
#      ifdef S_IFSOCK
#        define S_ISSOCK(m) (((m) & S_IFMT) == S_IFSOCK)
#      endif
#    endif
#  endif
#endif

#ifdef S_ISSOCK
    struct stat st;

    if (rb_stat(fname, &st) < 0) return Qfalse;
    if (S_ISSOCK(st.st_mode)) return Qtrue;

#endif
    return Qfalse;
}

Returns true if the named file is a socket.

file_name can be an IO object.

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

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"]

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

    FilePathValue(fname);
    fname = rb_str_encode_ospath(fname);
    if (stat_without_gvl(RSTRING_PTR(fname), &st) < 0) {
        rb_sys_fail_path(fname);
    }
    return rb_stat_new(&st);
}

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

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

static VALUE
rb_file_sticky_p(VALUE obj, VALUE fname)
{
#ifdef S_ISVTX
    return check3rdbyte(fname, S_ISVTX);
#else
    return Qnil;
#endif
}

Returns true if the named file has the sticky bit set.

file_name can be an IO object.

static VALUE
rb_file_s_symlink(VALUE klass, VALUE from, VALUE to)
{
    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);
    }
    return INT2FIX(0);
}

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

static VALUE
rb_file_symlink_p(VALUE obj, VALUE fname)
{
#ifndef S_ISLNK
#  ifdef _S_ISLNK
#    define S_ISLNK(m) _S_ISLNK(m)
#  else
#    ifdef _S_IFLNK
#      define S_ISLNK(m) (((m) & S_IFMT) == _S_IFLNK)
#    else
#      ifdef S_IFLNK
#        define S_ISLNK(m) (((m) & S_IFMT) == S_IFLNK)
#      endif
#    endif
#  endif
#endif

#ifdef S_ISLNK
    struct stat st;

    FilePathValue(fname);
    fname = rb_str_encode_ospath(fname);
    if (lstat_without_gvl(StringValueCStr(fname), &st) < 0) return Qfalse;
    if (S_ISLNK(st.st_mode)) return Qtrue;
#endif

    return Qfalse;
}

Returns true if the named file is a symbolic link.

static VALUE
rb_file_s_truncate(VALUE klass, VALUE path, VALUE len)
{
    struct truncate_arg ta;
    int r;

    ta.pos = NUM2POS(len);
    FilePathValue(path);
    path = rb_str_encode_ospath(path);
    ta.path = StringValueCStr(path);

    r = (int)(VALUE)rb_thread_call_without_gvl(nogvl_truncate, &ta,
                                                RUBY_UBF_IO, NULL);
    if (r < 0)
        rb_sys_fail_path(path);
    return INT2FIX(0);
#undef NUM2POS
}

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

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

    switch (argc) {
      case 0:
        omask = umask(0);
        umask(omask);
        break;
      case 1:
        omask = umask(NUM2MODET(argv[0]));
        break;
      default:
        rb_error_arity(argc, 0, 1);
    }
    return MODET2NUM(omask);
}

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

static VALUE
rb_file_s_unlink(int argc, VALUE *argv, VALUE klass)
{
    return apply2files(unlink_internal, argc, argv, 0);
}

Deletes the named files, returning the number of names passed as arguments. Raises an exception on any error. Since the underlying implementation relies on the unlink(2) system call, the type of exception raised depends on its error type (see linux.die.net/man/2/unlink) and has the form of e.g. Errno::ENOENT.

See also Dir::rmdir.

static VALUE
rb_file_s_utime(int argc, VALUE *argv, VALUE _)
{
    return utime_internal_i(argc, argv, FALSE);
}

Sets the access and modification times of each named file to the first two arguments. If a file is a symlink, this method acts upon its referent rather than the link itself; for the inverse behavior see File.lutime. Returns the number of file names in the argument list.

static VALUE
rb_file_world_readable_p(VALUE obj, VALUE fname)
{
#ifdef S_IROTH
    struct stat st;

    if (rb_stat(fname, &st) < 0) return Qnil;
    if ((st.st_mode & (S_IROTH)) == S_IROTH) {
        return UINT2NUM(st.st_mode & (S_IRUGO|S_IWUGO|S_IXUGO));
    }
#endif
    return Qnil;
}

If file_name is readable by others, returns an integer representing the file permission bits of file_name. Returns nil otherwise. The meaning of the bits is platform dependent; on Unix systems, see stat(2).

file_name can be an IO object.

File.world_readable?("/etc/passwd")           #=> 420
m = File.world_readable?("/etc/passwd")
sprintf("%o", m)                              #=> "644"

static VALUE
rb_file_world_writable_p(VALUE obj, VALUE fname)
{
#ifdef S_IWOTH
    struct stat st;

    if (rb_stat(fname, &st) < 0) return Qnil;
    if ((st.st_mode & (S_IWOTH)) == S_IWOTH) {
        return UINT2NUM(st.st_mode & (S_IRUGO|S_IWUGO|S_IXUGO));
    }
#endif
    return Qnil;
}

If file_name is writable by others, returns an integer representing the file permission bits of file_name. Returns nil otherwise. The meaning of the bits is platform dependent; on Unix systems, see stat(2).

file_name can be an IO object.

File.world_writable?("/tmp")                  #=> 511
m = File.world_writable?("/tmp")
sprintf("%o", m)                              #=> "777"

static VALUE
rb_file_writable_p(VALUE obj, VALUE fname)
{
    if (rb_eaccess(fname, W_OK) < 0) return Qfalse;
    return Qtrue;
}

Returns true if the named file is writable by the effective user and group id of this process. See eaccess(3).

Note that some OS-level security features may cause this to return true even though the file is not writable by the effective user/group.

static VALUE
rb_file_writable_real_p(VALUE obj, VALUE fname)
{
    if (rb_access(fname, W_OK) < 0) return Qfalse;
    return Qtrue;
}

Returns true if the named file is writable by the real user and group id of this process. See access(3).

Note that some OS-level security features may cause this to return true even though the file is not writable by the real user/group.

static VALUE
rb_file_zero_p(VALUE obj, VALUE fname)
{
    struct stat st;

    if (rb_stat(fname, &st) < 0) return Qfalse;
    if (st.st_size == 0) return Qtrue;
    return Qfalse;
}

Returns true if the named file exists and has a zero size.

file_name can be an IO object.

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);
    }
    return stat_atime(&st);
}

Returns the last access time (a Time object) for file, or epoch if file has not been accessed.

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

static VALUE
rb_file_birthtime(VALUE obj)
{
    rb_io_t *fptr;
    statx_data st;

    GetOpenFile(obj, fptr);
    if (fstatx_without_gvl(fptr->fd, &st, STATX_BTIME) == -1) {
        rb_sys_fail_path(fptr->pathv);
    }
    return statx_birthtime(&st, fptr->pathv);
}

Returns the birth time for file.

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

If the platform doesn't have birthtime, raises NotImplementedError.

static VALUE
rb_file_chmod(VALUE obj, VALUE vmode)
{
    rb_io_t *fptr;
    mode_t mode;
#if !defined HAVE_FCHMOD || !HAVE_FCHMOD
    VALUE path;
#endif

    mode = NUM2MODET(vmode);

    GetOpenFile(obj, fptr);
#ifdef HAVE_FCHMOD
    if (fchmod(fptr->fd, mode) == -1) {
        if (HAVE_FCHMOD || errno != ENOSYS)
            rb_sys_fail_path(fptr->pathv);
    }
    else {
        if (!HAVE_FCHMOD) return INT2FIX(0);
    }
#endif
#if !defined HAVE_FCHMOD || !HAVE_FCHMOD
    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);
}

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

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

    o = to_uid(owner);
    g = to_gid(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);
}

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)

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);
    }
    return stat_ctime(&st);
}

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

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

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

    if (fptr->mode & FMODE_WRITABLE) {
        rb_io_flush_raw(obj, 0);
    }
    while ((int)rb_thread_io_blocking_region(rb_thread_flock, op, fptr->fd) < 0) {
        int e = errno;
        switch (e) {
          case EAGAIN:
          case EACCES:
#if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN
          case EWOULDBLOCK:
#endif
            if (op1 & LOCK_NB) return Qfalse;

            time.tv_sec = 0;
            time.tv_usec = 100 * 1000; /* 0.1 sec */
            rb_thread_wait_for(time);
            rb_io_check_closed(fptr);
            continue;

          case EINTR:
#if defined(ERESTART)
          case ERESTART:
#endif
            break;

          default:
            rb_syserr_fail_path(e, fptr->pathv);
        }
    }
    return INT2FIX(0);
}

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
}

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

    GetOpenFile(obj, fptr);
    if (NIL_P(fptr->pathv)) return Qnil;
    path = rb_str_encode_ospath(fptr->pathv);
    if (lstat_without_gvl(RSTRING_PTR(path), &st) == -1) {
        rb_sys_fail_path(fptr->pathv);
    }
    return rb_stat_new(&st);
#else
    return rb_io_stat(obj);
#endif
}

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

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);
    }
    return stat_mtime(&st);
}

Returns the modification time for file.

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

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)) {
        rb_raise(rb_eIOError, "File is unnamed (TMPFILE?)");
    }

    return rb_str_dup(fptr->pathv);
}

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

The pathname may not point to the file corresponding to file. For instance, the pathname becomes void when the file has been moved or deleted.

This method raises IOError for a file created using File::Constants::TMPFILE because they don't have a pathname.

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

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_raw(obj, 0);
    }
    if (fstat(fptr->fd, &st) == -1) {
        rb_sys_fail_path(fptr->pathv);
    }
    return OFFT2NUM(st.st_size);
}

Returns the size of file in bytes.

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

static VALUE
rb_file_truncate(VALUE obj, VALUE len)
{
    rb_io_t *fptr;
    struct ftruncate_arg fa;

    fa.pos = NUM2POS(len);
    GetOpenFile(obj, fptr);
    if (!(fptr->mode & FMODE_WRITABLE)) {
        rb_raise(rb_eIOError, "not opened for writing");
    }
    rb_io_flush_raw(obj, 0);
    fa.fd = fptr->fd;
    if ((int)rb_thread_io_blocking_region(nogvl_ftruncate, &fa, fa.fd) < 0) {
        rb_sys_fail_path(fptr->pathv);
    }
    return INT2FIX(0);
#undef NUM2POS
}

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