This is a deprecated alias for each_char.
Reads at most maxlen bytes from the I/O stream. It blocks only if ios has no data immediately available. It doesn’t block if some data available.
If the optional outbuf argument is present, it must reference a String, which will receive the data. The outbuf will contain only the received data after the method call even if it is not empty at the beginning.
It raises EOFError on end of file.
readpartial is designed for streams such as pipe, socket, tty, etc. It blocks only when no data immediately available. This means that it blocks only when following all conditions hold.
the byte buffer in the IO object is empty.
the content of the stream is empty.
the stream is not reached to EOF.
When readpartial blocks, it waits data or EOF on the stream. If some data is reached, readpartial returns with the data. If EOF is reached, readpartial raises EOFError.
When readpartial doesn’t blocks, it returns or raises immediately. If the byte buffer is not empty, it returns the data in the buffer. Otherwise if the stream has some content, it returns the data in the stream. Otherwise if the stream is reached to EOF, it raises EOFError.
r, w = IO.pipe # buffer pipe content w << "abc" # "" "abc". r.readpartial(4096) #=> "abc" "" "" r.readpartial(4096) # blocks because buffer and pipe is empty. r, w = IO.pipe # buffer pipe content w << "abc" # "" "abc" w.close # "" "abc" EOF r.readpartial(4096) #=> "abc" "" EOF r.readpartial(4096) # raises EOFError r, w = IO.pipe # buffer pipe content w << "abc\ndef\n" # "" "abc\ndef\n" r.gets #=> "abc\n" "def\n" "" w << "ghi\n" # "def\n" "ghi\n" r.readpartial(4096) #=> "def\n" "" "ghi\n" r.readpartial(4096) #=> "ghi\n" "" ""
Note that readpartial behaves similar to sysread. The differences are:
If the byte buffer is not empty, read from the byte buffer instead of “sysread for buffered IO (IOError)”.
It doesn’t cause Errno::EWOULDBLOCK and Errno::EINTR. When readpartial meets EWOULDBLOCK and EINTR by read system call, readpartial retry the system call.
The latter means that readpartial is nonblocking-flag insensitive. It blocks on the situation IO#sysread causes Errno::EWOULDBLOCK as if the fd is blocking mode.
Reads a one-character string from ios. Raises an EOFError on end of file.
f = File.new("testfile") f.readchar #=> "h" f.readchar #=> "e"
Removes all the key-value pairs within gdbm.
By using binary search, finds a value in range which meets the given condition in O(log n) where n is the size of the range.
You can use this method in two use cases: a find-minimum mode and a find-any mode. In either case, the elements of the range must be monotone (or sorted) with respect to the block.
In find-minimum mode (this is a good choice for typical use case), the block must return true or false, and there must be a value x so that:
the block returns false for any value which is less than x, and
the block returns true for any value which is greater than or equal to x.
If x is within the range, this method returns the value x. Otherwise, it returns nil.
ary = [0, 4, 7, 10, 12] (0...ary.size).bsearch {|i| ary[i] >= 4 } #=> 1 (0...ary.size).bsearch {|i| ary[i] >= 6 } #=> 2 (0...ary.size).bsearch {|i| ary[i] >= 8 } #=> 3 (0...ary.size).bsearch {|i| ary[i] >= 100 } #=> nil (0.0...Float::INFINITY).bsearch {|x| Math.log(x) >= 0 } #=> 1.0
In find-any mode (this behaves like libc’s bsearch(3)), the block must return a number, and there must be two values x and y (x <= y) so that:
the block returns a positive number for v if v < x,
the block returns zero for v if x <= v < y, and
the block returns a negative number for v if y <= v.
This method returns any value which is within the intersection of the given range and x…y (if any). If there is no value that satisfies the condition, it returns nil.
ary = [0, 100, 100, 100, 200] (0..4).bsearch {|i| 100 - ary[i] } #=> 1, 2 or 3 (0..4).bsearch {|i| 300 - ary[i] } #=> nil (0..4).bsearch {|i| 50 - ary[i] } #=> nil
You must not mix the two modes at a time; the block must always return either true/false, or always return a number. It is undefined which value is actually picked up at each iteration.
Parses the given Ruby program read from src. src must be a String or an IO or a object with a gets method.
This method is called when weak warning is produced by the parser. fmt and args is printf style.
This method is called when strong warning is produced by the parser. fmt and args is printf style.
Start parsing and returns the value of the root action.
Return true if parsed source has errors.
Deletes all data from the database.
Returns the remote address as an array which contains address_family, port, hostname and numeric_address. It is defined for connection oriented socket such as TCPSocket.
If reverse_lookup is true or :hostname, hostname is obtained from numeric_address using reverse lookup. Or if it is false, or :numeric, hostname is same as numeric_address. Or if it is nil or omitted, obeys to ipsocket.do_not_reverse_lookup. See Socket.getaddrinfo also.
TCPSocket.open("www.ruby-lang.org", 80) {|sock| p sock.peeraddr #=> ["AF_INET", 80, "carbon.ruby-lang.org", "221.186.184.68"] p sock.peeraddr(true) #=> ["AF_INET", 80, "carbon.ruby-lang.org", "221.186.184.68"] p sock.peeraddr(false) #=> ["AF_INET", 80, "221.186.184.68", "221.186.184.68"] p sock.peeraddr(:hostname) #=> ["AF_INET", 80, "carbon.ruby-lang.org", "221.186.184.68"] p sock.peeraddr(:numeric) #=> ["AF_INET", 80, "221.186.184.68", "221.186.184.68"] }
Returns the remote address as an array which contains address_family and unix_path.
Example
serv = UNIXServer.new("/tmp/sock") c = UNIXSocket.new("/tmp/sock") p c.peeraddr #=> ["AF_UNIX", "/tmp/sock"]
This is a deprecated alias for each_char.
Returns the character position of the scan pointer. In the ‘reset’ position, this value is zero. In the ‘terminated’ position (i.e. the string is exhausted), this value is the size of the string.
In short, it’s a 0-based index into the string.
s = StringScanner.new("abcädeföghi") s.charpos # -> 0 s.scan_until(/ä/) # -> "abcä" s.pos # -> 5 s.charpos # -> 4
Returns array of WIN32OLE_VARIABLE objects which represent variables defined in OLE class.
tobj = WIN32OLE_TYPE.new('Microsoft Excel 9.0 Object Library', 'XlSheetType') vars = tobj.variables vars.each do |v| puts "#{v.name} = #{v.value}" end The result of above sample script is follows: xlChart = -4109 xlDialogSheet = -4116 xlExcel4IntlMacroSheet = 4 xlExcel4MacroSheet = 3 xlWorksheet = -4167
Returns the number which represents variable kind.
tobj = WIN32OLE_TYPE.new('Microsoft Excel 9.0 Object Library', 'XlSheetType')
variables = tobj.variables
variables.each do |variable|
puts "#{variable.name} #{variable.varkind}"
end
The result of above script is following:
xlChart 2
xlDialogSheet 2
xlExcel4IntlMacroSheet 2
xlExcel4MacroSheet 2
xlWorksheet 2
Returns OLE variant type.
obj = WIN32OLE_VARIANT.new("string") obj.vartype # => WIN32OLE::VARIANT::VT_BSTR
Removes all key-value pairs from hsh.
h = { "a" => 100, "b" => 200 } #=> {"a"=>100, "b"=>200} h.clear #=> {}
Searches through the hash comparing obj with the value using ==. Returns the first key-value pair (two-element array) that matches. See also Array#rassoc.
a = {1=> "one", 2 => "two", 3 => "three", "ii" => "two"} a.rassoc("two") #=> [2, "two"] a.rassoc("four") #=> nil
Removes every environment variable.
Returns an Array of the name and value of the environment variable with value or nil if the value cannot be found.