Receives up to maxlen bytes from socket using recvfrom(2) after O_NONBLOCK is set for the underlying file descriptor. flags is zero or more of the MSG_ options. The result, mesg, is the data received.
When recvfrom(2) returns 0, Socket#recv_nonblock returns an empty string as data. The meaning depends on the socket: EOF on TCP, empty packet on UDP, etc.
maxlen - the number of bytes to receive from the socket
flags - zero or more of the MSG_ options
buf - destination String buffer
options - keyword hash, supporting ‘exception: false`
serv = TCPServer.new("127.0.0.1", 0) af, port, host, addr = serv.addr c = TCPSocket.new(addr, port) s = serv.accept c.send "aaa", 0 begin # emulate blocking recv. p s.recv_nonblock(10) #=> "aaa" rescue IO::WaitReadable IO.select([s]) retry end
Refer to Socket#recvfrom for the exceptions that may be thrown if the call to recv_nonblock fails.
BasicSocket#recv_nonblock may raise any error corresponding to recvfrom(2) failure, including Errno::EWOULDBLOCK.
If the exception is Errno::EWOULDBLOCK or Errno::EAGAIN, it is extended by IO::WaitReadable. So IO::WaitReadable can be used to rescue the exceptions for retrying recv_nonblock.
By specifying a keyword argument exception to false, you can indicate that recv_nonblock should not raise an IO::WaitReadable exception, but return the symbol :wait_readable instead.
recvmsg receives a message using recvmsg(2) system call in non-blocking manner.
It is similar to BasicSocket#recvmsg but non-blocking flag is set before the system call and it doesn’t retry the system call.
By specifying a keyword argument exception to false, you can indicate that recvmsg_nonblock should not raise an IO::WaitReadable exception, but return the symbol :wait_readable instead.
creates a socket connected to the address of self.
If one or more arguments given as local_addr_args, it is used as the local address of the socket. local_addr_args is given for family_addrinfo to obtain actual address.
If local_addr_args is not given, the local address of the socket is not bound.
The optional last argument opts is options represented by a hash. opts may have following options:
specify the timeout in seconds.
If a block is given, it is called with the socket and the value of the block is returned. The socket is returned otherwise.
Addrinfo.tcp("www.ruby-lang.org", 80).connect_from("0.0.0.0", 4649) {|s| s.print "GET / HTTP/1.0\r\nHost: www.ruby-lang.org\r\n\r\n" puts s.read } # Addrinfo object can be taken for the argument. Addrinfo.tcp("www.ruby-lang.org", 80).connect_from(Addrinfo.tcp("0.0.0.0", 4649)) {|s| s.print "GET / HTTP/1.0\r\nHost: www.ruby-lang.org\r\n\r\n" puts s.read }
creates a socket connected to remote_addr_args and bound to self.
The optional last argument opts is options represented by a hash. opts may have following options:
specify the timeout in seconds.
If a block is given, it is called with the socket and the value of the block is returned. The socket is returned otherwise.
Addrinfo.tcp("0.0.0.0", 4649).connect_to("www.ruby-lang.org", 80) {|s| s.print "GET / HTTP/1.0\r\nHost: www.ruby-lang.org\r\n\r\n" puts s.read }
Returns true for IPv4 loopback address (127.0.0.0/8). It returns false otherwise.
Returns true for IPv4 multicast address (224.0.0.0/4). It returns false otherwise.
Returns true for IPv6 loopback address (::1). It returns false otherwise.
Returns true for IPv6 multicast address (ff00::/8). It returns false otherwise.
Returns true for IPv4-compatible IPv6 address (::/80). It returns false otherwise.
Returns the socket path as a string.
Addrinfo.unix("/tmp/sock").unix_path #=> "/tmp/sock"
Receives up to maxlen bytes from udpsocket using recvfrom(2) after O_NONBLOCK is set for the underlying file descriptor. flags is zero or more of the MSG_ options. The first element of the results, mesg, is the data received. The second element, sender_inet_addr, is an array to represent the sender address.
When recvfrom(2) returns 0, Socket#recvfrom_nonblock returns an empty string as data. It means an empty packet.
maxlen - the number of bytes to receive from the socket
flags - zero or more of the MSG_ options
outbuf - destination String buffer
options - keyword hash, supporting ‘exception: false`
require 'socket' s1 = UDPSocket.new s1.bind("127.0.0.1", 0) s2 = UDPSocket.new s2.bind("127.0.0.1", 0) s2.connect(*s1.addr.values_at(3,1)) s1.connect(*s2.addr.values_at(3,1)) s1.send "aaa", 0 begin # emulate blocking recvfrom p s2.recvfrom_nonblock(10) #=> ["aaa", ["AF_INET", 33302, "localhost.localdomain", "127.0.0.1"]] rescue IO::WaitReadable IO.select([s2]) retry end
Refer to Socket#recvfrom for the exceptions that may be thrown if the call to recvfrom_nonblock fails.
UDPSocket#recvfrom_nonblock may raise any error corresponding to recvfrom(2) failure, including Errno::EWOULDBLOCK.
If the exception is Errno::EWOULDBLOCK or Errno::EAGAIN, it is extended by IO::WaitReadable. So IO::WaitReadable can be used to rescue the exceptions for retrying recvfrom_nonblock.
By specifying a keyword argument exception to false, you can indicate that recvfrom_nonblock should not raise an IO::WaitReadable exception, but return the symbol :wait_readable instead.
Example
UNIXServer.open("/tmp/sock") {|serv| UNIXSocket.open("/tmp/sock") {|c| s = serv.accept c.send_io STDOUT stdout = s.recv_io p STDOUT.fileno #=> 1 p stdout.fileno #=> 7 stdout.puts "hello" # outputs "hello\n" to standard output. } }
klass will determine the class of io returned (using the IO.for_fd singleton method or similar). If klass is nil, an integer file descriptor is returned.
mode is the same as the argument passed to IO.for_fd
Closes the read end of a StringIO. Will raise an IOError if the receiver is not readable.
Closes the write end of a StringIO. Will raise an IOError if the receiver is not writeable.
Returns true if the stream is not readable, false otherwise.
Returns true if the stream is not writable, false otherwise.
Returns the Encoding object that represents the encoding of the file. If the stream is write mode and no encoding is specified, returns nil.
Returns the Encoding of the internal string if conversion is specified. Otherwise returns nil.
Specify the encoding of the StringIO as ext_enc. Use the default external encoding if ext_enc is nil. 2nd argument int_enc and optional hash opt argument are ignored; they are for API compatibility to IO.
Scans the string until the pattern is matched. Returns the substring up to and including the end of the match, advancing the scan pointer to that location. If there is no match, nil is returned.
s = StringScanner.new("Fri Dec 12 1975 14:39") s.scan_until(/1/) # -> "Fri Dec 1" s.pre_match # -> "Fri Dec " s.scan_until(/XYZ/) # -> nil
Advances the scan pointer until pattern is matched and consumed. Returns the number of bytes advanced, or nil if no match was found.
Look ahead to match pattern, and advance the scan pointer to the end of the match. Return the number of characters advanced, or nil if the match was unsuccessful.
It’s similar to scan_until, but without returning the intervening string.
s = StringScanner.new("Fri Dec 12 1975 14:39") s.skip_until /12/ # -> 10 s #
This returns the value that scan_until would return, without advancing the scan pointer. The match register is affected, though.
s = StringScanner.new("Fri Dec 12 1975 14:39") s.check_until /12/ # -> "Fri Dec 12" s.pos # -> 0 s.matched # -> 12
Mnemonic: it “checks” to see whether a scan_until will return a value.
Defines the constants of OLE Automation server as mod’s constants. The first argument is WIN32OLE object or type library name. If 2nd argument is omitted, the default is WIN32OLE. The first letter of Ruby’s constant variable name is upper case, so constant variable name of WIN32OLE object is capitalized. For example, the ‘xlTop’ constant of Excel is changed to ‘XlTop’ in WIN32OLE. If the first letter of constant variable is not [A-Z], then the constant is defined as CONSTANTS hash element.
module EXCEL_CONST end excel = WIN32OLE.new('Excel.Application') WIN32OLE.const_load(excel, EXCEL_CONST) puts EXCEL_CONST::XlTop # => -4160 puts EXCEL_CONST::CONSTANTS['_xlDialogChartSourceData'] # => 541 WIN32OLE.const_load(excel) puts WIN32OLE::XlTop # => -4160 module MSO end WIN32OLE.const_load('Microsoft Office 9.0 Object Library', MSO) puts MSO::MsoLineSingle # => 1
Translates and dispatches Windows message.