In Files

  • dir.c
  • file.c
  • io.c

File

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.

Public Class Methods

atime(file_name) => time click to toggle source

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

File.atime("testfile")   #=> Wed Apr 09 08:51:48 CDT 2003
 
               static VALUE
rb_file_s_atime(klass, fname)
    VALUE klass, fname;
{
    struct stat st;

    if (rb_stat(fname, &st) < 0)
        rb_sys_fail(StringValueCStr(fname));
    return rb_time_new(st.st_atime, 0);
}
            
basename(file_name [, suffix] ) → base_name click to toggle source

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"
 
               static VALUE
rb_file_s_basename(argc, argv)
    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) {
        StringValue(fext);
    }
    StringValue(fname);
    if (RSTRING_LEN(fname) == 0 || !*(name = RSTRING_PTR(fname)))
        return fname;

    p = ruby_find_basename(name, &f, &n);
    if (n >= 0) {
        if (NIL_P(fext) || !(f = rmext(p, n, StringValueCStr(fext)))) {
            f = n;
        }
        if (f == RSTRING_LEN(fname)) return fname;
    }

    basename = rb_str_new(p, f);
    OBJ_INFECT(basename, fname);
    return basename;
}
            
blockdev?(file_name) => true or false click to toggle source

Returns true if the named file is a block device.

 
               static VALUE
test_b(obj, fname)
    VALUE obj, 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;
}
            
chardev?(file_name) => true or false click to toggle source

Returns true if the named file is a character device.

 
               static VALUE
test_c(obj, fname)
    VALUE obj, 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;
}
            
chmod(mode_int, file_name, ... ) → integer click to toggle source

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_chmod(argc, argv)
    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 click to toggle source

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_chown(argc, argv)
    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;
    }
    else {
        arg.owner = NUM2INT(o);
    }
    if (NIL_P(g)) {
        arg.group = -1;
    }
    else {
        arg.group = NUM2INT(g);
    }

    n = apply2files(chown_internal, rest, &arg);
    return LONG2FIX(n);
}
            
ctime(file_name) => time click to toggle source

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

File.ctime("testfile")   #=> Wed Apr 09 08:53:13 CDT 2003
 
               static VALUE
rb_file_s_ctime(klass, fname)
    VALUE klass, fname;
{
    struct stat st;

    if (rb_stat(fname, &st) < 0)
        rb_sys_fail(RSTRING(fname)->ptr);
    return rb_time_new(st.st_ctime, 0);
}
            
delete(file_name, ...) => integer click to toggle source

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

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

    rb_secure(2);
    n = apply2files(unlink_internal, args, 0);
    return LONG2FIX(n);
}
            
directory?(file_name) => true or false click to toggle source

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

File.directory?(".")
 
               static VALUE
test_d(obj, fname)
    VALUE obj, 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;
}
            
dirname(file_name ) → dir_name click to toggle source

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"
 
               static VALUE
rb_file_s_dirname(klass, fname)
    VALUE klass, fname;
{
    const char *name, *root, *p;
    VALUE dirname;

    name = StringValueCStr(fname);
    root = skiproot(name);
#ifdef DOSISH_UNC
    if (root > name + 1 && isdirsep(*name))
        root = skipprefix(name = root - 2);
#else
    if (root > name + 1)
        name = root - 1;
#endif
    p = strrdirsep(root);
    if (!p) {
        p = root;
    }
    if (p == name)
        return rb_str_new2(".");
#ifdef DOSISH_DRIVE_LETTER
    if (has_drive_letter(name) && isdirsep(*(name + 2))) {
        const char *top = skiproot(name + 2);
        dirname = rb_str_new(name, 3);
        rb_str_cat(dirname, top, p - top);
    }
    else
#endif
    dirname = rb_str_new(name, p - name);
#ifdef DOSISH_DRIVE_LETTER
    if (has_drive_letter(name) && root == name + 2 && p - name == 2)
        rb_str_cat(dirname, ".", 1);
#endif
    OBJ_INFECT(dirname, fname);
    return dirname;
}
            
executable?(file_name) => true or false click to toggle source

Returns true if the named file is executable by the effective user id of this process.

 
               static VALUE
test_x(obj, fname)
    VALUE obj, fname;
{
    SafeStringValue(fname);
    if (eaccess(StringValueCStr(fname), X_OK) < 0) return Qfalse;
    return Qtrue;
}
            
executable_real?(file_name) => true or false click to toggle source

Returns true if the named file is executable by the real user id of this process.

 
               static VALUE
test_X(obj, fname)
    VALUE obj, fname;
{
    SafeStringValue(fname);
    if (access(StringValueCStr(fname), X_OK) < 0) return Qfalse;
    return Qtrue;
}
            
exist?(file_name) => true or false click to toggle source

Return true if the named file exists.

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

    if (rb_stat(fname, &st) < 0) return Qfalse;
    return Qtrue;
}
            
exists?(file_name) => true or false (obsolete) click to toggle source

Return true if the named file exists.

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

    if (rb_stat(fname, &st) < 0) return Qfalse;
    return Qtrue;
}
            
expand_path(file_name [, dir_string] ) → abs_file_name click to toggle source

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

    if (argc == 1) {
        return rb_file_expand_path(argv[0], Qnil);
    }
    rb_scan_args(argc, argv, "11", &fname, &dname);

    return rb_file_expand_path(fname, dname);
}
            
extname(path) → string click to toggle source

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

    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! */
    OBJ_INFECT(extname, fname);
    return extname;
}
            
file?(file_name) => true or false click to toggle source

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

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

    if (rb_stat(fname, &st) < 0) return Qfalse;
    if (S_ISREG(st.st_mode)) return Qtrue;
    return Qfalse;
}
            
fnmatch( pattern, path, [flags] ) => (true or false) click to toggle source
fnmatch?( pattern, path, [flags] ) => (true or false)

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
 
               static VALUE
file_s_fnmatch(argc, argv, obj)
    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);
    StringValue(path);

    if (fnmatch(RSTRING(pattern)->ptr, RSTRING(path)->ptr, flags) == 0)
        return Qtrue;

    return Qfalse;
}
            
fnmatch?( pattern, path, [flags] ) => (true or false) click to toggle source

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
 
               static VALUE
file_s_fnmatch(argc, argv, obj)
    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);
    StringValue(path);

    if (fnmatch(RSTRING(pattern)->ptr, RSTRING(path)->ptr, flags) == 0)
        return Qtrue;

    return Qfalse;
}
            
ftype(file_name) => string click to toggle source

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_s_ftype(klass, fname)
    VALUE klass, fname;
{
    struct stat st;

    SafeStringValue(fname);
    if (lstat(StringValueCStr(fname), &st) == -1) {
        rb_sys_fail(RSTRING(fname)->ptr);
    }

    return rb_file_ftype(&st);
}
            
grpowned?(file_name) => true or false click to toggle source

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.

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

    if (rb_stat(fname, &st) < 0) return Qfalse;
    if (group_member(st.st_gid)) return Qtrue;
#endif
    return Qfalse;
}
            
identical?(file_1, file_2) => true or false click to toggle source

Returns true if the named files are identical.

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
test_identical(obj, fname1, fname2)
    VALUE obj, fname1, fname2;
{
#ifndef DOSISH
    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;
#else
#ifdef _WIN32
    BY_HANDLE_FILE_INFORMATION st1, st2;
    HANDLE f1 = 0, f2 = 0;
#endif

    rb_secure(2);
#ifdef _WIN32
    f1 = w32_io_info(&fname1, &st1);
    if (f1 == INVALID_HANDLE_VALUE) return Qfalse;
    f2 = w32_io_info(&fname2, &st2);
    if (f1) CloseHandle(f1);
    if (f2 == INVALID_HANDLE_VALUE) return Qfalse;
    if (f2) CloseHandle(f2);

    if (st1.dwVolumeSerialNumber == st2.dwVolumeSerialNumber &&
        st1.nFileIndexHigh == st2.nFileIndexHigh &&
        st1.nFileIndexLow == st2.nFileIndexLow)
        return Qtrue;
    if (!f1 || !f2) return Qfalse;
    if (rb_w32_iswin95()) return Qfalse;
#else
    SafeStringValue(fname1);
    fname1 = rb_str_new4(fname1);
    SafeStringValue(fname2);
    if (access(RSTRING(fname1)->ptr, 0)) return Qfalse;
    if (access(RSTRING(fname2)->ptr, 0)) return Qfalse;
#endif
    fname1 = rb_file_expand_path(fname1, Qnil);
    fname2 = rb_file_expand_path(fname2, Qnil);
    if (RSTRING(fname1)->len != RSTRING(fname2)->len) return Qfalse;
    if (rb_memcicmp(RSTRING(fname1)->ptr, RSTRING(fname2)->ptr, RSTRING(fname1)->len))
        return Qfalse;
#endif
    return Qtrue;
}
            
join(string, ...) → path click to toggle source

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

File.join("usr", "mail", "gumby")   #=> "usr/mail/gumby"
 
               static VALUE
rb_file_s_join(klass, args)
    VALUE klass, args;
{
    return rb_file_join(args, separator);
}
            
lchmod(mode_int, file_name, ...) => integer click to toggle source

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_lchmod(argc, argv)
    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 click to toggle source

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_lchown(argc, argv)
    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;
    }
    else {
        arg.owner = NUM2INT(o);
    }
    if (NIL_P(g)) {
        arg.group = -1;
    }
    else {
        arg.group = NUM2INT(g);
    }

    n = apply2files(lchown_internal, rest, &arg);
    return LONG2FIX(n);
}
            
lstat(file_name) => stat click to toggle source

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

    SafeStringValue(fname);
    if (lstat(StringValueCStr(fname), &st) == -1) {
        rb_sys_fail(RSTRING(fname)->ptr);
    }
    return stat_new(&st);
#else
    return rb_file_s_stat(klass, fname);
#endif
}
            
mtime(file_name) => time click to toggle source

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

File.mtime("testfile")   #=> Tue Apr 08 12:58:04 CDT 2003
 
               static VALUE
rb_file_s_mtime(klass, fname)
    VALUE klass, fname;
{
    struct stat st;

    if (rb_stat(fname, &st) < 0)
        rb_sys_fail(RSTRING(fname)->ptr);
    return rb_time_new(st.st_mtime, 0);
}
            
new(filename, mode="r") => file click to toggle source
new(filename [, mode [, perm]]) => file

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

f = File.new("testfile", "r")
f = File.new("newfile",  "w+")
f = File.new("newfile", File::CREAT|File::TRUNC|File::RDWR, 0644)
 
               static VALUE
rb_file_initialize(argc, argv, io)
    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_convert_type(argv[0], T_FIXNUM, "Fixnum", "to_int");

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

    return io;
}
            
owned?(file_name) => true or false click to toggle source

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

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

    if (rb_stat(fname, &st) < 0) return Qfalse;
    if (st.st_uid == geteuid()) return Qtrue;
    return Qfalse;
}
            
pipe?(file_name) => true or false click to toggle source

Returns true if the named file is a pipe.

 
               static VALUE
test_p(obj, fname)
    VALUE obj, 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;
}
            
readable?(file_name) => true or false click to toggle source

Returns true if the named file is readable by the effective user id of this process.

 
               static VALUE
test_r(obj, fname)
    VALUE obj, fname;
{
    SafeStringValue(fname);
    if (eaccess(StringValueCStr(fname), R_OK) < 0) return Qfalse;
    return Qtrue;
}
            
readable_real?(file_name) => true or false click to toggle source

Returns true if the named file is readable by the real user id of this process.

 
               static VALUE
test_R(obj, fname)
    VALUE obj, fname;
{
    SafeStringValue(fname);
    if (access(StringValueCStr(fname), R_OK) < 0) return Qfalse;
    return Qtrue;
}
            
rename(old_name, new_name) => 0 click to toggle source

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_s_rename(klass, from, to)
    VALUE klass, from, to;
{
    const char *src, *dst;
    SafeStringValue(from);
    SafeStringValue(to);

    src = StringValueCStr(from);
    dst = StringValueCStr(to);
#if defined __CYGWIN__
    errno = 0;
#endif
    if (rename(src, dst) < 0) {
#if defined DOSISH && !defined _WIN32
        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);
        }
#endif
        sys_fail2(from, to);
    }

    return INT2FIX(0);
}
            
setgid?(file_name) => true or false click to toggle source

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

 
               static VALUE
test_sgid(obj, fname)
    VALUE obj, fname;
{
#ifdef S_ISGID
    return check3rdbyte(fname, S_ISGID);
#else
    return Qfalse;
#endif
}
            
setuid?(file_name) => true or false click to toggle source

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

 
               static VALUE
test_suid(obj, fname)
    VALUE obj, fname;
{
#ifdef S_ISUID
    return check3rdbyte(fname, S_ISUID);
#else
    return Qfalse;
#endif
}
            
size(file_name) => integer click to toggle source

Returns the size of file_name.

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

    if (rb_stat(fname, &st) < 0)
        rb_sys_fail(StringValueCStr(fname));
    return OFFT2NUM(st.st_size);
}
            
size?(file_name) => Integer or nil click to toggle source

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

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

    if (rb_stat(fname, &st) < 0) return Qnil;
    if (st.st_size == 0) return Qnil;
    return OFFT2NUM(st.st_size);
}
            
socket?(file_name) => true or false click to toggle source

Returns true if the named file is a socket.

 
               static VALUE
test_S(obj, fname)
    VALUE obj, fname;
{
#ifndef S_ISSOCK
#  ifdef _S_ISSOCK
#    define S_ISSOCK(m) _S_ISSOCK(m)
#  elif defined __BORLANDC__
#    ifdef _S_IFSOCK
#      define S_ISSOCK(m) (((unsigned short)(m) & S_IFMT) == _S_IFSOCK)
#    else
#      ifdef S_IFSOCK
#        define S_ISSOCK(m) (((unsigned short)(m) & S_IFMT) == S_IFSOCK)
#      endif
#    endif
#  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;
}
            
split(file_name) => array click to toggle source

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_split(klass, path)
    VALUE klass, path;
{
    StringValue(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) => stat click to toggle source

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_s_stat(klass, fname)
    VALUE klass, fname;
{
    struct stat st;

    SafeStringValue(fname);
    if (rb_stat(fname, &st) < 0) {
        rb_sys_fail(StringValueCStr(fname));
    }
    return stat_new(&st);
}
            
sticky?(file_name) => true or false click to toggle source

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

 
               static VALUE
test_sticky(obj, fname)
    VALUE obj, fname;
{
#ifdef S_ISVTX
    return check3rdbyte(fname, S_ISVTX);
#else
    return Qnil;
#endif
}
            
truncate(file_name, integer) => 0 click to toggle source

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_truncate(klass, path, len)
    VALUE klass, path, len;
{
    off_t pos;

    rb_secure(2);
    pos = NUM2OFFT(len);
    SafeStringValue(path);

#ifdef HAVE_TRUNCATE
    if (truncate(StringValueCStr(path), pos) < 0)
        rb_sys_fail(RSTRING(path)->ptr);
#else
# ifdef HAVE_CHSIZE
    {
        int tmpfd;

#  ifdef _WIN32
        if ((tmpfd = open(StringValueCStr(path), O_RDWR)) < 0) {
            rb_sys_fail(RSTRING(path)->ptr);
        }
#  else
        if ((tmpfd = open(StringValueCStr(path), 0)) < 0) {
            rb_sys_fail(RSTRING(path)->ptr);
        }
#  endif
        if (chsize(tmpfd, pos) < 0) {
            close(tmpfd);
            rb_sys_fail(RSTRING(path)->ptr);
        }
        close(tmpfd);
    }
# else
    rb_notimplement();
# endif
#endif
    return INT2FIX(0);
}
            
umask() => integer click to toggle source
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
 
               static VALUE
rb_file_s_umask(argc, argv)
    int argc;
    VALUE *argv;
{
    int omask = 0;

    rb_secure(2);
    if (argc == 0) {
        omask = umask(0);
        umask(omask);
    }
    else if (argc == 1) {
        omask = umask(NUM2INT(argv[0]));
    }
    else {
        rb_raise(rb_eArgError, "wrong number of arguments");
    }
    return INT2FIX(omask);
}
            
utime(atime, mtime, file_name,...) => integer click to toggle source

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.

 
               static VALUE
rb_file_s_utime(argc, argv)
    int argc;
    VALUE *argv;
{
    VALUE atime, mtime, rest;
    struct timeval tvs[2], *tvp = NULL;
    long n;

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

    if (!NIL_P(atime) || !NIL_P(mtime)) {
        tvp = tvs;
        tvp[0] = rb_time_timeval(atime);
        tvp[1] = rb_time_timeval(mtime);
    }

    n = apply2files(utime_internal, rest, tvp);
    return LONG2FIX(n);
}
            
writable?(file_name) => true or false click to toggle source

Returns true if the named file is writable by the effective user id of this process.

 
               static VALUE
test_w(obj, fname)
    VALUE obj, fname;
{
    SafeStringValue(fname);
    if (eaccess(StringValueCStr(fname), W_OK) < 0) return Qfalse;
    return Qtrue;
}
            
writable_real?(file_name) => true or false click to toggle source

Returns true if the named file is writable by the real user id of this process.

 
               static VALUE
test_W(obj, fname)
    VALUE obj, fname;
{
    SafeStringValue(fname);
    if (access(StringValueCStr(fname), W_OK) < 0) return Qfalse;
    return Qtrue;
}
            
zero?(file_name) => true or false click to toggle source

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

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

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

Public Instance Methods

atime => time click to toggle source

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

    GetOpenFile(obj, fptr);
    if (fstat(fileno(fptr->f), &st) == -1) {
        rb_sys_fail(fptr->path);
    }
    return rb_time_new(st.st_atime, 0);
}
            
chmod(mode_int) => 0 click to toggle source

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_chmod(obj, vmode)
    VALUE obj, vmode;
{
    rb_io_t *fptr;
    int mode;

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

    GetOpenFile(obj, fptr);
#ifdef HAVE_FCHMOD
    if (fchmod(fileno(fptr->f), mode) == -1)
        rb_sys_fail(fptr->path);
#else
    if (!fptr->path) return Qnil;
    if (chmod(fptr->path, mode) == -1)
        rb_sys_fail(fptr->path);
#endif

    return INT2FIX(0);
}
            
chown(owner_int, group_int ) => 0 click to toggle source

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_chown(obj, owner, group)
    VALUE obj, owner, group;
{
    rb_io_t *fptr;
    int o, g;

    rb_secure(2);
    o = NIL_P(owner) ? -1 : NUM2INT(owner);
    g = NIL_P(group) ? -1 : NUM2INT(group);
    GetOpenFile(obj, fptr);
#if defined(DJGPP) || defined(__CYGWIN32__) || defined(_WIN32) || defined(__EMX__)
    if (!fptr->path) return Qnil;
    if (chown(fptr->path, o, g) == -1)
        rb_sys_fail(fptr->path);
#else
    if (fchown(fileno(fptr->f), o, g) == -1)
        rb_sys_fail(fptr->path);
#endif

    return INT2FIX(0);
}
            
ctime → time click to toggle source

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

File.new("testfile").ctime   #=> Wed Apr 09 08:53:14 CDT 2003
 
               static VALUE
rb_file_ctime(obj)
    VALUE obj;
{
    rb_io_t *fptr;
    struct stat st;

    GetOpenFile(obj, fptr);
    if (fstat(fileno(fptr->f), &st) == -1) {
        rb_sys_fail(fptr->path);
    }
    return rb_time_new(st.st_ctime, 0);
}
            
flock (locking_constant ) => 0 or false click to toggle source

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:

File.new("testfile").flock(File::LOCK_UN)   #=> 0
 
               static VALUE
rb_file_flock(obj, operation)
    VALUE obj;
    VALUE operation;
{
#ifndef __CHECKER__
    rb_io_t *fptr;
    int op;

    rb_secure(2);
    op = NUM2INT(operation);
    GetOpenFile(obj, fptr);

    if (fptr->mode & FMODE_WRITABLE) {
        fflush(GetWriteFile(fptr));
    }
  retry:
    if (flock(fileno(fptr->f), op) < 0) {
        switch (errno) {
          case EAGAIN:
          case EACCES:
#if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN
          case EWOULDBLOCK:
#endif
              return Qfalse;
          case EINTR:
#if defined(ERESTART)
          case ERESTART:
#endif
            goto retry;
        }
        rb_sys_fail(fptr->path);
    }
#endif
    return INT2FIX(0);
}
            
lstat => stat click to toggle source

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_lstat(obj)
    VALUE obj;
{
#ifdef HAVE_LSTAT
    rb_io_t *fptr;
    struct stat st;

    rb_secure(2);
    GetOpenFile(obj, fptr);
    if (!fptr->path) return Qnil;
    if (lstat(fptr->path, &st) == -1) {
        rb_sys_fail(fptr->path);
    }
    return stat_new(&st);
#else
    return rb_io_stat(obj);
#endif
}
            
mtime → time click to toggle source

Returns the modification time for file.

File.new("testfile").mtime   #=> Wed Apr 09 08:53:14 CDT 2003
 
               static VALUE
rb_file_mtime(obj)
    VALUE obj;
{
    rb_io_t *fptr;
    struct stat st;

    GetOpenFile(obj, fptr);
    if (fstat(fileno(fptr->f), &st) == -1) {
        rb_sys_fail(fptr->path);
    }
    return rb_time_new(st.st_mtime, 0);
}
            
path → filename click to toggle source

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

    fptr = RFILE(rb_io_taint_check(obj))->fptr;
    rb_io_check_initialized(fptr);
    if (!fptr->path) return Qnil;
    return rb_tainted_str_new2(fptr->path);
}
            
truncate(integer) => 0 click to toggle source

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
 
               static VALUE
rb_file_truncate(obj, len)
    VALUE obj, len;
{
    rb_io_t *fptr;
    FILE *f;
    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");
    }
    f = GetWriteFile(fptr);
    fflush(f);
    fseeko(f, (off_t)0, SEEK_CUR);
#ifdef HAVE_FTRUNCATE
    if (ftruncate(fileno(f), pos) < 0)
        rb_sys_fail(fptr->path);
#else
# ifdef HAVE_CHSIZE
    if (chsize(fileno(f), pos) < 0)
        rb_sys_fail(fptr->path);
# else
    rb_notimplement();
# endif
#endif
    return INT2FIX(0);
}
            

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