Changes the current working directory of the process to the given string. When called without an argument, changes the directory to the value of the environment variable HOME, or LOGDIR. SystemCallError (probably Errno::ENOENT) if the target directory does not exist.
If a block is given, it is passed the name of the new current directory, and the block is executed with that as the current directory. The original working directory is restored when the block exits. The return value of chdir is the value of the block. chdir blocks can be nested, but in a multi-threaded program an error will be raised if a thread attempts to open a chdir block while another thread has one open.
Dir.chdir("/var/spool/mail") puts Dir.pwd Dir.chdir("/tmp") do puts Dir.pwd Dir.chdir("/usr") do puts Dir.pwd end puts Dir.pwd end puts Dir.pwd
produces:
/var/spool/mail /tmp /usr /tmp /var/spool/mail
Changes this process’s idea of the file system root. Only a privileged process may make this call. Not available on all platforms. On Unix systems, see chroot(2) for more information.
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
*cMatches 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('?', '/', 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
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
*cMatches 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('?', '/', 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
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
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")
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.
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.
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
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 true if the named file is a symbolic link.
Iterates over the block according to how this Enumerator was constructed. If no block and no arguments are given, returns self.
"Hello, world!".scan(/\w+/) #=> ["Hello", "world"] "Hello, world!".to_enum(:scan, /\w+/).to_a #=> ["Hello", "world"] "Hello, world!".to_enum(:scan).each(/\w+/).to_a #=> ["Hello", "world"] obj = Object.new def obj.each_arg(a, b=:b, *rest) yield a yield b yield rest :method_returned end enum = obj.to_enum :each_arg, :a, :x enum.each.to_a #=> [:a, :x, []] enum.each.equal?(enum) #=> true enum.each { |elm| elm } #=> :method_returned enum.each(:y, :z).to_a #=> [:a, :x, [:y, :z]] enum.each(:y, :z).equal?(enum) #=> false enum.each(:y, :z) { |elm| elm } #=> :method_returned
Returns a hash of parsed elements.
Raise an ArgumentError when the string length is longer than limit. You can stop this check by passing ‘limit: nil`, but note that it may take a long time to parse.
Creates a new Date object by parsing from a string according to some typical XML Schema formats.
Date.xmlschema('2001-02-03') #=> #<Date: 2001-02-03 ...>
Raise an ArgumentError when the string length is longer than limit. You can stop this check by passing ‘limit: nil`, but note that it may take a long time to parse.
This method is equivalent to strftime(‘%F’).
Creates a new DateTime object by parsing from a string according to some typical XML Schema formats.
DateTime.xmlschema('2001-02-03T04:05:06+07:00') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...>
Raise an ArgumentError when the string length is longer than limit. You can stop this check by passing ‘limit: nil`, but note that it may take a long time to parse.
This method is equivalent to strftime(‘%FT%T%:z’). The optional argument n is the number of digits for fractional seconds.
DateTime.parse('2001-02-03T04:05:06.123456789+07:00').iso8601(9) #=> "2001-02-03T04:05:06.123456789+07:00"
Parses date as a dateTime defined by the XML Schema and converts it to a Time object. The format is a restricted version of the format defined by ISO 8601.
ArgumentError is raised if date is not compliant with the format or if the Time class cannot represent specified date.
See xmlschema for more information on this format.
require 'time' Time.xmlschema("2011-10-05T22:26:12-04:00") #=> 2011-10-05 22:26:12-04:00
You must require ‘time’ to use this method.
Returns a string which represents the time as a dateTime defined by XML Schema:
CCYY-MM-DDThh:mm:ssTZD CCYY-MM-DDThh:mm:ss.sssTZD
where TZD is Z or [+-]hh:mm.
If self is a UTC time, Z is used as TZD. [+-]hh:mm is used otherwise.
fractional_digits specifies a number of digits to use for fractional seconds. Its default value is 0.
require 'time' t = Time.now t.iso8601 # => "2011-10-05T22:26:12-04:00"
You must require ‘time’ to use this method.
Return a value from the database by locating the key string provided. If the key is not found, returns ifnone. If ifnone is not given, raises IndexError.
Calls the block once for each [key, value] pair in the database. Returns self.
Yields the value of each struct member in order. If no block is given an enumerator is returned.
Customer = Struct.new(:name, :address, :zip) joe = Customer.new("Joe Smith", "123 Maple, Anytown NC", 12345) joe.each {|x| puts(x) }
Produces:
Joe Smith 123 Maple, Anytown NC 12345
Reads and returns a character in raw mode.
See IO#raw for details on the parameters.
You must require ‘io/console’ to use this method.