Results for: "optionparser"

Gets a socket option. These are protocol and system specific, see your local system documentation for details. The option is returned as a Socket::Option object.

Parameters

• level is an integer, usually one of the SOL_ constants such as Socket::SOL_SOCKET, or a protocol level. A string or symbol of the name, possibly without prefix, is also accepted.

• optname is an integer, usually one of the SO_ constants, such as Socket::SO_REUSEADDR. A string or symbol of the name, possibly without prefix, is also accepted.

Examples

Some socket options are integers with boolean values, in this case getsockopt could be called like this:

reuseaddr = sock.getsockopt(:SOCKET, :REUSEADDR).bool

optval = sock.getsockopt(Socket::SOL_SOCKET,Socket::SO_REUSEADDR)
optval = optval.unpack "i"
reuseaddr = optval[0] == 0 ? false : true

Some socket options are integers with numeric values, in this case getsockopt could be called like this:

ipttl = sock.getsockopt(:IP, :TTL).int

optval = sock.getsockopt(Socket::IPPROTO_IP, Socket::IP_TTL)
ipttl = optval.unpack1("i")

Option values may be structs. Decoding them can be complex as it involves examining your system headers to determine the correct definition. An example is a +struct linger+, which may be defined in your system headers as:

struct linger {
  int l_onoff;
  int l_linger;
};

In this case getsockopt could be called like this:

# Socket::Option knows linger structure.
onoff, linger = sock.getsockopt(:SOCKET, :LINGER).linger

optval =  sock.getsockopt(Socket::SOL_SOCKET, Socket::SO_LINGER)
onoff, linger = optval.unpack "ii"
onoff = onoff == 0 ? false : true

Runs the early binding method to get property. The 1st argument specifies dispatch ID, the 2nd argument specifies the array of arguments, the 3rd argument specifies the array of the type of arguments.

excel = WIN32OLE.new('Excel.Application')
puts excel._getproperty(558, [], []) # same effect as puts excel.visible

Returns the value that determines whether headers are used; used for parsing; see {Option headers}:

CSV.new('').headers # => nil

• With no block, installs a field converter (a Proc).

• With a block, defines and installs a custom field converter.

• Returns the Array of installed field converters.

• Argument converter_name, if given, should be the name of an existing field converter.

See Field Converters.

With no block, installs a field converter:

csv = CSV.new('')
csv.convert(:integer)
csv.convert(:float)
csv.convert(:date)
csv.converters # => [:integer, :float, :date]

The block, if given, is called for each field:

• Argument field is the field value.

• Argument field_info is a CSV::FieldInfo object containing details about the field.

The examples here assume the prior execution of:

string = "foo,0\nbar,1\nbaz,2\n"
path = 't.csv'
File.write(path, string)

Example giving a block:

csv = CSV.open(path)
csv.convert {|field, field_info| p [field, field_info]; field.upcase }
csv.read # => [["FOO", "0"], ["BAR", "1"], ["BAZ", "2"]]

Output:

["foo", #<struct CSV::FieldInfo index=0, line=1, header=nil>]
["0", #<struct CSV::FieldInfo index=1, line=1, header=nil>]
["bar", #<struct CSV::FieldInfo index=0, line=2, header=nil>]
["1", #<struct CSV::FieldInfo index=1, line=2, header=nil>]
["baz", #<struct CSV::FieldInfo index=0, line=3, header=nil>]
["2", #<struct CSV::FieldInfo index=1, line=3, header=nil>]

The block need not return a String object:

csv = CSV.open(path)
csv.convert {|field, field_info| field.to_sym }
csv.read # => [[:foo, :"0"], [:bar, :"1"], [:baz, :"2"]]

If converter_name is given, the block is not called:

csv = CSV.open(path)
csv.convert(:integer) {|field, field_info| fail 'Cannot happen' }
csv.read # => [["foo", 0], ["bar", 1], ["baz", 2]]

Raises a parse-time exception if converter_name is not the name of a built-in field converter:

csv = CSV.open(path)
csv.convert(:nosuch) => [nil]
# Raises NoMethodError (undefined method `arity' for nil:NilClass)
csv.read

Returns an array of member names of the data class:

Measure = Data.define(:amount, :unit)
Measure.members # => [:amount, :unit]

Returns the member names from self as an array:

Measure = Data.define(:amount, :unit)
distance = Measure[10, 'km']

distance.members #=> [:amount, :unit]

Returns the number of online processors.

The result is intended as the number of processes to use all available processors.

This method is implemented using:

• sched_getaffinity(): Linux

• sysconf(_SC_NPROCESSORS_ONLN): GNU/Linux, NetBSD, FreeBSD, OpenBSD, DragonFly BSD, OpenIndiana, Mac OS X, AIX

Example:

require 'etc'
p Etc.nprocessors #=> 4

The result might be smaller number than physical cpus especially when ruby process is bound to specific cpus. This is intended for getting better parallel processing.

Example: (Linux)

linux$ taskset 0x3 ./ruby -retc -e "p Etc.nprocessors"  #=> 2

See any remaining errors held in queue.

Any errors you see here are probably due to a bug in Ruby’s OpenSSL implementation.

See Process.getpriority.

Examples:

Process.setpriority(Process::PRIO_USER, 0, 19)    # => 0
Process.setpriority(Process::PRIO_PROCESS, 0, 19) # => 0
Process.getpriority(Process::PRIO_USER, 0)        # => 19
Process.getpriority(Process::PRIO_PROCESS, 0)     # => 19

Not available on all platforms.

Sets the process title that appears on the ps(1) command. Not necessarily effective on all platforms. No exception will be raised regardless of the result, nor will NotImplementedError be raised even if the platform does not support the feature.

Calling this method does not affect the value of $0.

Process.setproctitle('myapp: worker #%d' % worker_id)

This method first appeared in Ruby 2.1 to serve as a global variable free means to change the process title.

Compile a NumberedParametersNode node

Dispatch enter and leave events for NumberedParametersNode nodes and continue walking the tree.

Copy a NumberedParametersNode node

Adds a section with title and content to the parser help view. Used for adding command arguments and default arguments.

Add the install/update options to the option parser.

Add local/remote options to the command line parser.

Add the –bulk-threshold option

Add the –update-sources option

Makes the set compare its elements by their identity and returns self. This method may not be supported by all subclasses of Set.

Returns true if the set will compare its elements by their identity. Also see Set#compare_by_identity.

creates TCP/IP server sockets for host and port. host is optional.

If no block given, it returns an array of listening sockets.

If a block is given, the block is called with the sockets. The value of the block is returned. The socket is closed when this method returns.

If port is 0, actual port number is chosen dynamically. However all sockets in the result has same port number.

# tcp_server_sockets returns two sockets.
sockets = Socket.tcp_server_sockets(1296)
p sockets #=> [#<Socket:fd 3>, #<Socket:fd 4>]

# The sockets contains IPv6 and IPv4 sockets.
sockets.each {|s| p s.local_address }
#=> #<Addrinfo: [::]:1296 TCP>
#   #<Addrinfo: 0.0.0.0:1296 TCP>

# IPv6 and IPv4 socket has same port number, 53114, even if it is chosen dynamically.
sockets = Socket.tcp_server_sockets(0)
sockets.each {|s| p s.local_address }
#=> #<Addrinfo: [::]:53114 TCP>
#   #<Addrinfo: 0.0.0.0:53114 TCP>

# The block is called with the sockets.
Socket.tcp_server_sockets(0) {|sockets|
  p sockets #=> [#<Socket:fd 3>, #<Socket:fd 4>]
}