If file_name is writable by others, returns an integer representing the file permission bits of file_name. Returns nil otherwise. The meaning of the bits is platform dependent; on Unix systems, see stat(2).
file_name can be an IO object.
File.world_writable?("/tmp") #=> 511 m = File.world_writable?("/tmp") sprintf("%o", m) #=> "777"
Returns the list of private methods accessible to obj. If the all parameter is set to false, only those methods in the receiver will be listed.
Returns an array of instance variable names for the receiver. Note that simply defining an accessor does not create the corresponding instance variable.
class Fred attr_accessor :a1 def initialize @iv = 3 end end Fred.new.instance_variables #=> [:@iv]
Return a list of the local variable names defined where this NameError exception was raised.
Internal use only.
Return true if the caused method was called as private.
When this module is included in another, Ruby calls append_features in this module, passing it the receiving module in mod. Ruby’s default implementation is to add the constants, methods, and module variables of this module to mod if this module has not already been added to mod or one of its ancestors. See also Module#include.
When this module is prepended in another, Ruby calls prepend_features in this module, passing it the receiving module in mod. Ruby’s default implementation is to overlay the constants, methods, and module variables of this module to mod if this module has not already been added to mod or one of its ancestors. See also Module#prepend.
Creates an accessor method to allow assignment to the attribute symbol.id2name. String arguments are converted to symbols. Returns an array of defined method names as symbols.
Returns an array of the names of class variables in mod. This includes the names of class variables in any included modules, unless the inherit parameter is set to false.
class One @@var1 = 1 end class Two < One @@var2 = 2 end One.class_variables #=> [:@@var1] Two.class_variables #=> [:@@var2, :@@var1] Two.class_variables(false) #=> [:@@var2]
Makes a list of existing constants private.
Returns true if the given year is a leap year in the proleptic Gregorian calendar, false otherwise:
Date.gregorian_leap?(2000) # => true Date.gregorian_leap?(2001) # => false
Date.leap? is an alias for Date.gregorian_leap?.
Related: Date.julian_leap?.
Waits until IO is writable and returns a truthy value or a falsy value when times out.
You must require ‘io/wait’ to use this method.
Closes the stream for writing if open for writing; returns nil. See Open and Closed Streams.
Flushes any buffered writes to the operating system before closing.
If the stream was opened by IO.popen and is also closed for reading, sets global variable $? (child exit status).
IO.popen('ruby', 'r+') do |pipe| puts pipe.closed? pipe.close_read puts pipe.closed? pipe.close_write puts $? puts pipe.closed? end
Output:
false false pid 15044 exit 0 true
Related: IO#close, IO#close_read, IO#closed?.
Writes the given string to ios using the write(2) system call after O_NONBLOCK is set for the underlying file descriptor.
It returns the number of bytes written.
write_nonblock just calls the write(2) system call. It causes all errors the write(2) system call causes: Errno::EWOULDBLOCK, Errno::EINTR, etc. The result may also be smaller than string.length (partial write). The caller should care such errors and partial write.
If the exception is Errno::EWOULDBLOCK or Errno::EAGAIN, it is extended by IO::WaitWritable. So IO::WaitWritable can be used to rescue the exceptions for retrying write_nonblock.
# Creates a pipe. r, w = IO.pipe # write_nonblock writes only 65536 bytes and return 65536. # (The pipe size is 65536 bytes on this environment.) s = "a" * 100000 p w.write_nonblock(s) #=> 65536 # write_nonblock cannot write a byte and raise EWOULDBLOCK (EAGAIN). p w.write_nonblock("b") # Resource temporarily unavailable (Errno::EAGAIN)
If the write buffer is not empty, it is flushed at first.
When write_nonblock raises an exception kind of IO::WaitWritable, write_nonblock should not be called until io is writable for avoiding busy loop. This can be done as follows.
begin result = io.write_nonblock(string) rescue IO::WaitWritable, Errno::EINTR IO.select(nil, [io]) retry end
Note that this doesn’t guarantee to write all data in string. The length written is reported as result and it should be checked later.
On some platforms such as Windows, write_nonblock is not supported according to the kind of the IO object. In such cases, write_nonblock raises Errno::EBADF.
By specifying a keyword argument exception to false, you can indicate that write_nonblock should not raise an IO::WaitWritable exception, but return the symbol :wait_writable instead.
Returns a hash representing named captures of self (see Named Captures):
Each key is the name of a named capture.
Each value is an array of integer indexes for that named capture.
Examples:
/(?<foo>.)(?<bar>.)/.named_captures # => {"foo"=>[1], "bar"=>[2]} /(?<foo>.)(?<foo>.)/.named_captures # => {"foo"=>[1, 2]} /(.)(.)/.named_captures # => {}
USE OF RIPPER LIBRARY ONLY.
Strips up to width leading whitespaces from input, and returns the stripped column width.
USE OF RIPPER LIBRARY ONLY.
Strips up to width leading whitespaces from input, and returns the stripped column width.
Disallows further write using shutdown system call.
UNIXSocket.pair {|s1, s2| s1.print "ping" s1.close_write p s2.read #=> "ping" s2.print "pong" s2.close p s1.read #=> "pong" }
creates an Addrinfo object from the arguments.
The arguments are interpreted as similar to self.
Addrinfo.tcp("0.0.0.0", 4649).family_addrinfo("www.ruby-lang.org", 80) #=> #<Addrinfo: 221.186.184.68:80 TCP (www.ruby-lang.org:80)> Addrinfo.unix("/tmp/sock").family_addrinfo("/tmp/sock2") #=> #<Addrinfo: /tmp/sock2 SOCK_STREAM>