Sets the Fiber scheduler for the current thread. If the scheduler is set, non-blocking fibers (created by Fiber.new with blocking: false, or by Fiber.schedule) call that scheduler’s hook methods on potentially blocking operations, and the current thread will call scheduler’s close method on finalization (allowing the scheduler to properly manage all non-finished fibers).
scheduler can be an object of any class corresponding to Fiber::Scheduler. Its implementation is up to the user.
See also the “Non-blocking fibers” section in class docs.
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"
A simple example of using dir_string is as follows.
File.expand_path("ruby", "/usr/bin") #=> "/usr/bin/ruby"
A more complex example which also resolves parent directory is as follows. Suppose we are in bin/mygem and want the absolute path of lib/mygem.rb.
File.expand_path("../../lib/mygem.rb", __FILE__) #=> ".../path/to/project/lib/mygem.rb"
So first it resolves the parent of __FILE__, that is bin/, then go to the parent, the root of the project and appends lib/mygem.rb.
Returns whether ASCII-compatible or not.
Encoding::UTF_8.ascii_compatible? #=> true Encoding::UTF_16BE.ascii_compatible? #=> false
Sets the named constant to the given object, returning that object. Creates a new constant if no constant with the given name previously existed.
Math.const_set("HIGH_SCHOOL_PI", 22.0/7.0) #=> 3.14285714285714 Math::HIGH_SCHOOL_PI - Math::PI #=> 0.00126448926734968
If sym or str is not a valid constant name a NameError will be raised with a warning “wrong constant name”.
Object.const_set('foobar', 42) #=> NameError: wrong constant name foobar
Returns a 2-length array; the first item is the result of BigDecimal#precision and the second one is of BigDecimal#scale.
See BigDecimal#precision. See BigDecimal#scale.
Return the number of seconds the specified time zone differs from UTC.
Numeric time zones that include minutes, such as -10:00 or +1330 will work, as will simpler hour-only time zones like -10 or +13.
Textual time zones listed in ZoneOffset are also supported.
If the time zone does not match any of the above, zone_offset will check if the local time zone (both with and without potential Daylight Saving Time changes being in effect) matches zone. Specifying a value for year will change the year used to find the local time zone.
If zone_offset is unable to determine the offset, nil will be returned.
require 'time' Time.zone_offset("EST") #=> -18000
You must require ‘time’ to use this method.
Attempts to convert object into an IO object via method to_io; returns the new IO object if successful, or nil otherwise:
IO.try_convert(STDOUT) # => #<IO:<STDOUT>> IO.try_convert(ARGF) # => #<IO:<STDIN>> IO.try_convert('STDOUT') # => nil
Returns object if it is a regexp:
Regexp.try_convert(/re/) # => /re/
Otherwise if object responds to :to_regexp, calls object.to_regexp and returns the result.
Returns nil if object does not respond to :to_regexp.
Regexp.try_convert('re') # => nil
Raises an exception unless object.to_regexp returns a regexp.
Returns true if matching against re can be done in linear time to the input string.
Regexp.linear_time?(/re/) # => true
Note that this is a property of the ruby interpreter, not of the argument regular expression. Identical regexp can or cannot run in linear time depending on your ruby binary. Neither forward nor backward compatibility is guaranteed about the return value of this method. Our current algorithm is (*1) but this is subject to change in the future. Alternative implementations can also behave differently. They might always return false for everything.
Clone internal hash.
Accepts an incoming connection using accept(2) after O_NONBLOCK is set for the underlying file descriptor. It returns an array containing the accepted socket for the incoming connection, client_socket, and an Addrinfo, client_addrinfo.
# In one script, start this first require 'socket' include Socket::Constants socket = Socket.new(AF_INET, SOCK_STREAM, 0) sockaddr = Socket.sockaddr_in(2200, 'localhost') socket.bind(sockaddr) socket.listen(5) begin # emulate blocking accept client_socket, client_addrinfo = socket.accept_nonblock rescue IO::WaitReadable, Errno::EINTR IO.select([socket]) retry end puts "The client said, '#{client_socket.readline.chomp}'" client_socket.puts "Hello from script one!" socket.close # In another script, start this second require 'socket' include Socket::Constants socket = Socket.new(AF_INET, SOCK_STREAM, 0) sockaddr = Socket.sockaddr_in(2200, 'localhost') socket.connect(sockaddr) socket.puts "Hello from script 2." puts "The server said, '#{socket.readline.chomp}'" socket.close
Refer to Socket#accept for the exceptions that may be thrown if the call to accept_nonblock fails.
Socket#accept_nonblock may raise any error corresponding to accept(2) failure, including Errno::EWOULDBLOCK.
If the exception is Errno::EWOULDBLOCK, Errno::EAGAIN, Errno::ECONNABORTED or Errno::EPROTO, it is extended by IO::WaitReadable. So IO::WaitReadable can be used to rescue the exceptions for retrying accept_nonblock.
By specifying a keyword argument exception to false, you can indicate that accept_nonblock should not raise an IO::WaitReadable exception, but return the symbol :wait_readable instead.
yield socket and client address for each a connection accepted via given sockets.
The arguments are a list of sockets. The individual argument should be a socket or an array of sockets.
This method yields the block sequentially. It means that the next connection is not accepted until the block returns. So concurrent mechanism, thread for example, should be used to service multiple clients at a time.
Requests a connection to be made on the given remote_sockaddr after O_NONBLOCK is set for the underlying file descriptor. Returns 0 if successful, otherwise an exception is raised.
# +remote_sockaddr+ - the +struct+ sockaddr contained in a string or Addrinfo object
# Pull down Google's web page require 'socket' include Socket::Constants socket = Socket.new(AF_INET, SOCK_STREAM, 0) sockaddr = Socket.sockaddr_in(80, 'www.google.com') begin # emulate blocking connect socket.connect_nonblock(sockaddr) rescue IO::WaitWritable IO.select(nil, [socket]) # wait 3-way handshake completion begin socket.connect_nonblock(sockaddr) # check connection failure rescue Errno::EISCONN end end socket.write("GET / HTTP/1.0\r\n\r\n") results = socket.read
Refer to Socket#connect for the exceptions that may be thrown if the call to connect_nonblock fails.
Socket#connect_nonblock may raise any error corresponding to connect(2) failure, including Errno::EINPROGRESS.
If the exception is Errno::EINPROGRESS, it is extended by IO::WaitWritable. So IO::WaitWritable can be used to rescue the exceptions for retrying connect_nonblock.
By specifying a keyword argument exception to false, you can indicate that connect_nonblock should not raise an IO::WaitWritable exception, but return the symbol :wait_writable instead.
# Socket#connect
sendmsg_nonblock sends a message using sendmsg(2) system call in non-blocking manner.
It is similar to BasicSocket#sendmsg but the 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 sendmsg_nonblock should not raise an IO::WaitWritable exception, but return the symbol :wait_writable instead.
creates a new Socket connected to the address of local_addrinfo.
If local_addrinfo is nil, the address of the socket is not bound.
The timeout specify the seconds for timeout. Errno::ETIMEDOUT is raised when timeout occur.
If a block is given the created socket is yielded for each address.
Returns the IP address and port number as 2-element array.
Addrinfo.tcp("127.0.0.1", 80).ip_unpack #=> ["127.0.0.1", 80] Addrinfo.tcp("::1", 80).ip_unpack #=> ["::1", 80]
Accepts an incoming connection using accept(2) after O_NONBLOCK is set for the underlying file descriptor. It returns an accepted TCPSocket for the incoming connection.
require 'socket' serv = TCPServer.new(2202) begin # emulate blocking accept sock = serv.accept_nonblock rescue IO::WaitReadable, Errno::EINTR IO.select([serv]) retry end # sock is an accepted socket.
Refer to Socket#accept for the exceptions that may be thrown if the call to TCPServer#accept_nonblock fails.
TCPServer#accept_nonblock may raise any error corresponding to accept(2) failure, including Errno::EWOULDBLOCK.
If the exception is Errno::EWOULDBLOCK, Errno::EAGAIN, Errno::ECONNABORTED, Errno::EPROTO, it is extended by IO::WaitReadable. So IO::WaitReadable can be used to rescue the exceptions for retrying accept_nonblock.
By specifying a keyword argument exception to false, you can indicate that accept_nonblock should not raise an IO::WaitReadable exception, but return the symbol :wait_readable instead.
Accepts an incoming connection using accept(2) after O_NONBLOCK is set for the underlying file descriptor. It returns an accepted UNIXSocket for the incoming connection.
require 'socket' serv = UNIXServer.new("/tmp/sock") begin # emulate blocking accept sock = serv.accept_nonblock rescue IO::WaitReadable, Errno::EINTR IO.select([serv]) retry end # sock is an accepted socket.
Refer to Socket#accept for the exceptions that may be thrown if the call to UNIXServer#accept_nonblock fails.
UNIXServer#accept_nonblock may raise any error corresponding to accept(2) failure, including Errno::EWOULDBLOCK.
If the exception is Errno::EWOULDBLOCK, Errno::EAGAIN, Errno::ECONNABORTED or Errno::EPROTO, it is extended by IO::WaitReadable. So IO::WaitReadable can be used to rescue the exceptions for retrying accept_nonblock.
By specifying a keyword argument exception to false, you can indicate that accept_nonblock should not raise an IO::WaitReadable exception, but return the symbol :wait_readable instead.
Sends io as file descriptor passing.
s1, s2 = UNIXSocket.pair s1.send_io STDOUT stdout = s2.recv_io p STDOUT.fileno #=> 1 p stdout.fileno #=> 6 stdout.puts "hello" # outputs "hello\n" to standard output.
io may be any kind of IO object or integer file descriptor.