Class: File

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:

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

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

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

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

Returns 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

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
}

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

Returns the modification time for file.

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

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"

Returns the size of file in bytes.

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

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"

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