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"
Returns the string representation of the path
File.path(File::NULL) #=> "/dev/null" File.path(Pathname.new("/tmp")) #=> "/tmp"
Returns the list of name and aliases of the encoding.
Encoding::WINDOWS_31J.names #=> ["Windows-31J", "CP932", "csWindows31J", "SJIS", "PCK"]
Return the name associated with this NameError exception.
Returns the name of the module mod. Returns nil for anonymous modules.
Returns pathname configuration variable using fpathconf().
name should be a constant under Etc which begins with PC_.
The return value is an integer or nil. nil means indefinite limit. (fpathconf() returns -1 but errno is not set.)
require 'etc' IO.pipe {|r, w| p w.pathconf(Etc::PC_PIPE_BUF) #=> 4096 }
Returns name of associated terminal (tty) if io is not a tty. Returns nil otherwise.
Returns the path associated with the IO, or nil if there is no path associated with the IO. It is not guaranteed that the path exists on the filesystem.
$stdin.path # => "<STDIN>" File.open("testfile") {|f| f.path} # => "testfile"
Returns an array of names of captures (see Named Captures):
/(?<foo>.)(?<bar>.)(?<baz>.)/.names # => ["foo", "bar", "baz"] /(?<foo>.)(?<foo>.)/.names # => ["foo"] /(.)(.)/.names # => []
Returns a frozen string representation of self (not including the leading colon):
:foo.name # => "foo" :foo.name.frozen? # => true
Related: Symbol#to_s, Symbol#inspect.
Obtains the port number for service_name.
If protocol_name is not given, “tcp” is assumed.
Socket.getservbyname("smtp") #=> 25 Socket.getservbyname("shell") #=> 514 Socket.getservbyname("syslog", "udp") #=> 514
Obtains name information for sockaddr.
sockaddr should be one of follows.
packed sockaddr string such as Socket.sockaddr_in(80, “127.0.0.1”)
3-elements array such as [“AF_INET”, 80, “127.0.0.1”]
4-elements array such as [“AF_INET”, 80, ignored, “127.0.0.1”]
flags should be bitwise OR of Socket::NI_* constants.
Note: The last form is compatible with IPSocket#addr and IPSocket#peeraddr.
Socket.getnameinfo(Socket.sockaddr_in(80, "127.0.0.1")) #=> ["localhost", "www"] Socket.getnameinfo(["AF_INET", 80, "127.0.0.1"]) #=> ["localhost", "www"] Socket.getnameinfo(["AF_INET", 80, "localhost", "127.0.0.1"]) #=> ["localhost", "www"]
If Addrinfo object is preferred, use Addrinfo#getnameinfo.
Returns the local address of the socket as a sockaddr string.
TCPServer.open("127.0.0.1", 15120) {|serv| p serv.getsockname #=> "\x02\x00;\x10\x7F\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00" }
If Addrinfo object is preferred over the binary string, use BasicSocket#local_address.
Returns the remote address of the socket as a sockaddr string.
TCPServer.open("127.0.0.1", 1440) {|serv| c = TCPSocket.new("127.0.0.1", 1440) s = serv.accept p s.getpeername #=> "\x02\x00\x82u\x7F\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00" }
If Addrinfo object is preferred over the binary string, use BasicSocket#remote_address.
returns the canonical name as a string.
nil is returned if no canonical name.
The canonical name is set by Addrinfo.getaddrinfo when AI_CANONNAME is specified.
list = Addrinfo.getaddrinfo("www.ruby-lang.org", 80, :INET, :STREAM, nil, Socket::AI_CANONNAME) p list[0] #=> #<Addrinfo: 221.186.184.68:80 TCP carbon.ruby-lang.org (www.ruby-lang.org)> p list[0].canonname #=> "carbon.ruby-lang.org"
returns nodename and service as a pair of strings. This converts struct sockaddr in addrinfo to textual representation.
flags should be bitwise OR of Socket::NI_??? constants.
Addrinfo.tcp("127.0.0.1", 80).getnameinfo #=> ["localhost", "www"] Addrinfo.tcp("127.0.0.1", 80).getnameinfo(Socket::NI_NUMERICSERV) #=> ["localhost", "80"]
Returns the path of the local address of unixsocket.
s = UNIXServer.new("/tmp/sock") p s.path #=> "/tmp/sock"
Returns the current filename. “-” is returned when the current file is STDIN.
For example:
$ echo "foo" > foo $ echo "bar" > bar $ echo "glark" > glark $ ruby argf.rb foo bar glark ARGF.filename #=> "foo" ARGF.read(5) #=> "foo\nb" ARGF.filename #=> "bar" ARGF.skip ARGF.filename #=> "glark"
Returns the current filename. “-” is returned when the current file is STDIN.
For example:
$ echo "foo" > foo $ echo "bar" > bar $ echo "glark" > glark $ ruby argf.rb foo bar glark ARGF.filename #=> "foo" ARGF.read(5) #=> "foo\nb" ARGF.filename #=> "bar" ARGF.skip ARGF.filename #=> "glark"
Returns an array of the capture names (see Named Captures):
m = /(?<foo>.)(?<bar>.)(?<baz>.)/.match("hoge") # => #<MatchData "hog" foo:"h" bar:"o" baz:"g"> m.names # => ["foo", "bar", "baz"] m = /foo/.match('foo') # => #<MatchData "foo"> m.names # => [] # No named captures.
Equivalent to:
m = /(?<foo>.)(?<bar>.)(?<baz>.)/.match("hoge") m.regexp.names # => ["foo", "bar", "baz"]
Looks up the hostname of address.
Looks up all hostnames for address.