This is a deprecated alias for each_char
.
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.
Return a Regexp
object that is the union of the given patterns, i.e., will match any of its parts. The patterns can be Regexp
objects, in which case their options will be preserved, or Strings. If no patterns are given, returns /(?!)/
. The behavior is unspecified if any given pattern contains capture.
Regexp.union #=> /(?!)/ Regexp.union("penzance") #=> /penzance/ Regexp.union("a+b*c") #=> /a\+b\*c/ Regexp.union("skiing", "sledding") #=> /skiing|sledding/ Regexp.union(["skiing", "sledding"]) #=> /skiing|sledding/ Regexp.union(/dogs/, /cats/i) #=> /(?-mix:dogs)|(?i-mx:cats)/
Note: the arguments for ::union
will try to be converted into a regular expression literal via to_regexp.
Returns clean pathname of self
with consecutive slashes and useless dots removed. The filesystem is not accessed.
If consider_symlink
is true
, then a more conservative algorithm is used to avoid breaking symbolic linkages. This may retain more ..
entries than absolutely necessary, but without accessing the filesystem, this can’t be avoided.
See Pathname#realpath
.
Returns an array of interface addresses. An element of the array is an instance of Socket::Ifaddr
.
This method can be used to find multicast-enabled interfaces:
pp Socket.getifaddrs.reject {|ifaddr| !ifaddr.addr.ip? || (ifaddr.flags & Socket::IFF_MULTICAST == 0) }.map {|ifaddr| [ifaddr.name, ifaddr.ifindex, ifaddr.addr] } #=> [["eth0", 2, #<Addrinfo: 221.186.184.67>], # ["eth0", 2, #<Addrinfo: fe80::216:3eff:fe95:88bb%eth0>]]
Example result on GNU/Linux:
pp Socket.getifaddrs #=> [#<Socket::Ifaddr lo UP,LOOPBACK,RUNNING,0x10000 PACKET[protocol=0 lo hatype=772 HOST hwaddr=00:00:00:00:00:00]>, # #<Socket::Ifaddr eth0 UP,BROADCAST,RUNNING,MULTICAST,0x10000 PACKET[protocol=0 eth0 hatype=1 HOST hwaddr=00:16:3e:95:88:bb] broadcast=PACKET[protocol=0 eth0 hatype=1 HOST hwaddr=ff:ff:ff:ff:ff:ff]>, # #<Socket::Ifaddr sit0 NOARP PACKET[protocol=0 sit0 hatype=776 HOST hwaddr=00:00:00:00]>, # #<Socket::Ifaddr lo UP,LOOPBACK,RUNNING,0x10000 127.0.0.1 netmask=255.0.0.0>, # #<Socket::Ifaddr eth0 UP,BROADCAST,RUNNING,MULTICAST,0x10000 221.186.184.67 netmask=255.255.255.240 broadcast=221.186.184.79>, # #<Socket::Ifaddr lo UP,LOOPBACK,RUNNING,0x10000 ::1 netmask=ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff>, # #<Socket::Ifaddr eth0 UP,BROADCAST,RUNNING,MULTICAST,0x10000 fe80::216:3eff:fe95:88bb%eth0 netmask=ffff:ffff:ffff:ffff::>]
Example result on FreeBSD:
pp Socket.getifaddrs #=> [#<Socket::Ifaddr usbus0 UP,0x10000 LINK[usbus0]>, # #<Socket::Ifaddr re0 UP,BROADCAST,RUNNING,MULTICAST,0x800 LINK[re0 3a:d0:40:9a:fe:e8]>, # #<Socket::Ifaddr re0 UP,BROADCAST,RUNNING,MULTICAST,0x800 10.250.10.18 netmask=255.255.255.? (7 bytes for 16 bytes sockaddr_in) broadcast=10.250.10.255>, # #<Socket::Ifaddr re0 UP,BROADCAST,RUNNING,MULTICAST,0x800 fe80:2::38d0:40ff:fe9a:fee8 netmask=ffff:ffff:ffff:ffff::>, # #<Socket::Ifaddr re0 UP,BROADCAST,RUNNING,MULTICAST,0x800 2001:2e8:408:10::12 netmask=UNSPEC>, # #<Socket::Ifaddr plip0 POINTOPOINT,MULTICAST,0x800 LINK[plip0]>, # #<Socket::Ifaddr lo0 UP,LOOPBACK,RUNNING,MULTICAST LINK[lo0]>, # #<Socket::Ifaddr lo0 UP,LOOPBACK,RUNNING,MULTICAST ::1 netmask=ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff>, # #<Socket::Ifaddr lo0 UP,LOOPBACK,RUNNING,MULTICAST fe80:4::1 netmask=ffff:ffff:ffff:ffff::>, # #<Socket::Ifaddr lo0 UP,LOOPBACK,RUNNING,MULTICAST 127.0.0.1 netmask=255.?.?.? (5 bytes for 16 bytes sockaddr_in)>]
Obtains the port number for service_name.
If protocol_name is not given, “tcp” is assumed.
Socket.getservbyname("smtp") #=> 25 Socket.getservbyname("shell") #=> 514 Socket.getservbyname("syslog", "udp") #=> 514
Obtains the port number for port.
If protocol_name is not given, “tcp” is assumed.
Socket.getservbyport(80) #=> "www" Socket.getservbyport(514, "tcp") #=> "shell" Socket.getservbyport(514, "udp") #=> "syslog"
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.
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.
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.unpack("i")[0]
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
This is a deprecated alias for each_char
.
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 array of WIN32OLE_PARAM
object corresponding with method parameters.
tobj = WIN32OLE_TYPE.new('Microsoft Excel 9.0 Object Library', 'Workbook') method = WIN32OLE_METHOD.new(tobj, 'SaveAs') p method.params # => [Filename, FileFormat, Password, WriteResPassword, ReadOnlyRecommended, CreateBackup, AccessMode, ConflictResolution, AddToMru, TextCodepage, TextVisualLayout]
This is a deprecated alias for each_char
.
Returns nil
if headers will not be used, true
if they will but have not yet been read, or the actual headers after they have been read. See CSV::new
for details.
You can use this method to install a CSV::Converters
built-in, or provide a block that handles a custom conversion.
If you provide a block that takes one argument, it will be passed the field and is expected to return the converted value or the field itself. If your block takes two arguments, it will also be passed a CSV::FieldInfo
Struct
, containing details about the field. Again, the block should return a converted field or the field itself.
Returns true
if this is an hermitian matrix. Raises an error if matrix is not square.
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
.
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
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.
Adds a section with title
and content
to the parser help view. Used for adding command arguments and default arguments.