Returns ProgID if it exists. If not found, then returns nil.
tobj = WIN32OLE_TYPE.new('Microsoft Excel 9.0 Object Library', 'Application') puts tobj.progid # => Excel.Application.9
Returns a time returned by POSIX clock_gettime
() function.
p Process.clock_gettime(Process::CLOCK_MONOTONIC) #=> 896053.968060096
clock_id
specifies a kind of clock. It is specified as a constant which begins with Process::CLOCK_
such as Process::CLOCK_REALTIME
and Process::CLOCK_MONOTONIC
.
The supported constants depends on OS and version. Ruby provides following types of clock_id
if available.
CLOCK_REALTIME
SUSv2 to 4, Linux 2.5.63, FreeBSD 3.0, NetBSD 2.0, OpenBSD 2.1, macOS 10.12
CLOCK_MONOTONIC
SUSv3 to 4, Linux 2.5.63, FreeBSD 3.0, NetBSD 2.0, OpenBSD 3.4, macOS 10.12
CLOCK_PROCESS_CPUTIME_ID
SUSv3 to 4, Linux 2.5.63, FreeBSD 9.3, OpenBSD 5.4, macOS 10.12
CLOCK_THREAD_CPUTIME_ID
SUSv3 to 4, Linux 2.5.63, FreeBSD 7.1, OpenBSD 5.4, macOS 10.12
CLOCK_VIRTUAL
FreeBSD 3.0, OpenBSD 2.1
CLOCK_PROF
FreeBSD 3.0, OpenBSD 2.1
CLOCK_REALTIME_FAST
FreeBSD 8.1
CLOCK_REALTIME_PRECISE
FreeBSD 8.1
CLOCK_REALTIME_COARSE
Linux 2.6.32
CLOCK_REALTIME_ALARM
Linux 3.0
CLOCK_MONOTONIC_FAST
FreeBSD 8.1
CLOCK_MONOTONIC_PRECISE
FreeBSD 8.1
CLOCK_MONOTONIC_COARSE
Linux 2.6.32
CLOCK_MONOTONIC_RAW
Linux 2.6.28, macOS 10.12
CLOCK_MONOTONIC_RAW_APPROX
macOS 10.12
CLOCK_BOOTTIME
Linux 2.6.39
CLOCK_BOOTTIME_ALARM
Linux 3.0
CLOCK_UPTIME
FreeBSD 7.0, OpenBSD 5.5
CLOCK_UPTIME_FAST
FreeBSD 8.1
CLOCK_UPTIME_RAW
macOS 10.12
CLOCK_UPTIME_RAW_APPROX
macOS 10.12
CLOCK_UPTIME_PRECISE
FreeBSD 8.1
CLOCK_SECOND
FreeBSD 8.1
CLOCK_TAI
Linux 3.10
Note that SUS stands for Single Unix Specification. SUS contains POSIX and clock_gettime
is defined in the POSIX part. SUS defines CLOCK_REALTIME
mandatory but CLOCK_MONOTONIC
, CLOCK_PROCESS_CPUTIME_ID
and CLOCK_THREAD_CPUTIME_ID
are optional.
Also, several symbols are accepted as clock_id
. There are emulations for clock_gettime
().
For example, Process::CLOCK_REALTIME
is defined as :GETTIMEOFDAY_BASED_CLOCK_REALTIME
when clock_gettime
() is not available.
Emulations for CLOCK_REALTIME
:
Use gettimeofday() defined by SUS. (SUSv4 obsoleted it, though.) The resolution is 1 microsecond.
Use time() defined by ISO C. The resolution is 1 second.
Emulations for CLOCK_MONOTONIC
:
Use mach_absolute_time(), available on Darwin. The resolution is CPU dependent.
Use the result value of times() defined by POSIX. POSIX defines it as “times() shall return the elapsed real time, in clock ticks, since an arbitrary point in the past (for example, system start-up time)”. For example, GNU/Linux returns a value based on jiffies and it is monotonic. However, 4.4BSD uses gettimeofday() and it is not monotonic. (FreeBSD uses clock_gettime
(CLOCK_MONOTONIC
) instead, though.) The resolution is the clock tick. “getconf CLK_TCK” command shows the clock ticks per second. (The clock ticks per second is defined by HZ macro in older systems.) If it is 100 and clock_t is 32 bits integer type, the resolution is 10 millisecond and cannot represent over 497 days.
Emulations for CLOCK_PROCESS_CPUTIME_ID
:
Use getrusage() defined by SUS. getrusage() is used with RUSAGE_SELF to obtain the time only for the calling process (excluding the time for child processes). The result is addition of user time (ru_utime) and system time (ru_stime). The resolution is 1 microsecond.
Use times() defined by POSIX. The result is addition of user time (tms_utime) and system time (tms_stime). tms_cutime and tms_cstime are ignored to exclude the time for child processes. The resolution is the clock tick. “getconf CLK_TCK” command shows the clock ticks per second. (The clock ticks per second is defined by HZ macro in older systems.) If it is 100, the resolution is 10 millisecond.
Use clock() defined by ISO C. The resolution is 1/CLOCKS_PER_SEC. CLOCKS_PER_SEC is the C-level macro defined by time.h. SUS defines CLOCKS_PER_SEC is 1000000. Non-Unix systems may define it a different value, though. If CLOCKS_PER_SEC is 1000000 as SUS, the resolution is 1 microsecond. If CLOCKS_PER_SEC is 1000000 and clock_t is 32 bits integer type, it cannot represent over 72 minutes.
If the given clock_id
is not supported, Errno::EINVAL is raised.
unit
specifies a type of the return value.
number of seconds as a float (default)
number of milliseconds as a float
number of microseconds as a float
number of seconds as an integer
number of milliseconds as an integer
number of microseconds as an integer
number of nanoseconds as an integer
The underlying function, clock_gettime
(), returns a number of nanoseconds. Float
object (IEEE 754 double) is not enough to represent the return value for CLOCK_REALTIME
. If the exact nanoseconds value is required, use :nanoseconds
as the unit
.
The origin (zero) of the returned value varies. For example, system start up time, process start up time, the Epoch, etc.
The origin in CLOCK_REALTIME
is defined as the Epoch (1970-01-01 00:00:00 UTC). But some systems count leap seconds and others doesn’t. So the result can be interpreted differently across systems. Time.now
is recommended over CLOCK_REALTIME
.
Returns the time resolution returned by POSIX clock_getres
() function.
clock_id
specifies a kind of clock. See the document of Process.clock_gettime
for details.
clock_id
can be a symbol as Process.clock_gettime
. However the result may not be accurate. For example, Process.clock_getres(:GETTIMEOFDAY_BASED_CLOCK_REALTIME)
returns 1.0e-06 which means 1 microsecond, but actual resolution can be more coarse.
If the given clock_id
is not supported, Errno::EINVAL is raised.
unit
specifies a type of the return value. Process.clock_getres
accepts unit
as Process.clock_gettime
. The default value, :float_second
, is also same as Process.clock_gettime
.
Process.clock_getres
also accepts :hertz
as unit
. :hertz
means a the reciprocal of :float_second
.
:hertz
can be used to obtain the exact value of the clock ticks per second for times() function and CLOCKS_PER_SEC for clock() function.
Process.clock_getres(:TIMES_BASED_CLOCK_PROCESS_CPUTIME_ID, :hertz)
returns the clock ticks per second.
Process.clock_getres(:CLOCK_BASED_CLOCK_PROCESS_CPUTIME_ID, :hertz)
returns CLOCKS_PER_SEC.
p Process.clock_getres(Process::CLOCK_MONOTONIC) #=> 1.0e-09
Returns the list of protected methods accessible to obj. If the all parameter is set to false
, only those methods in the receiver will be listed.
Returns true if the set is a proper superset of the given set.
Returns true if the set is a proper subset of the given set.
Receives up to maxlen bytes from socket
using recvfrom(2) after O_NONBLOCK is set for the underlying file descriptor. flags is zero or more of the MSG_
options. The first element of the results, mesg, is the data received. The second element, sender_addrinfo, contains protocol-specific address information of the sender.
When recvfrom(2) returns 0, Socket#recvfrom_nonblock
returns an empty string as data. The meaning depends on the socket: EOF on TCP, empty packet on UDP, etc.
maxlen
- the maximum number of bytes to receive from the socket
flags
- zero or more of the MSG_
options
outbuf
- destination String
buffer
opts
- keyword hash, supporting ‘exception: false`
# In one file, 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) client, client_addrinfo = socket.accept begin # emulate blocking recvfrom pair = client.recvfrom_nonblock(20) rescue IO::WaitReadable IO.select([client]) retry end data = pair[0].chomp puts "I only received 20 bytes '#{data}'" sleep 1 socket.close # In another file, 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 "Watch this get cut short!" socket.close
Refer to Socket#recvfrom
for the exceptions that may be thrown if the call to recvfrom_nonblock fails.
Socket#recvfrom_nonblock
may raise any error corresponding to recvfrom(2) failure, including Errno::EWOULDBLOCK.
If the exception is Errno::EWOULDBLOCK or Errno::EAGAIN, it is extended by IO::WaitReadable
. So IO::WaitReadable
can be used to rescue the exceptions for retrying recvfrom_nonblock.
By specifying a keyword argument exception to false
, you can indicate that recvfrom_nonblock
should not raise an IO::WaitReadable
exception, but return the symbol :wait_readable
instead.
Receives up to maxlen bytes from udpsocket
using recvfrom(2) after O_NONBLOCK is set for the underlying file descriptor. flags is zero or more of the MSG_
options. The first element of the results, mesg, is the data received. The second element, sender_inet_addr, is an array to represent the sender address.
When recvfrom(2) returns 0, Socket#recvfrom_nonblock
returns an empty string as data. It means an empty packet.
maxlen
- the number of bytes to receive from the socket
flags
- zero or more of the MSG_
options
outbuf
- destination String
buffer
options
- keyword hash, supporting ‘exception: false`
require 'socket' s1 = UDPSocket.new s1.bind("127.0.0.1", 0) s2 = UDPSocket.new s2.bind("127.0.0.1", 0) s2.connect(*s1.addr.values_at(3,1)) s1.connect(*s2.addr.values_at(3,1)) s1.send "aaa", 0 begin # emulate blocking recvfrom p s2.recvfrom_nonblock(10) #=> ["aaa", ["AF_INET", 33302, "localhost.localdomain", "127.0.0.1"]] rescue IO::WaitReadable IO.select([s2]) retry end
Refer to Socket#recvfrom
for the exceptions that may be thrown if the call to recvfrom_nonblock fails.
UDPSocket#recvfrom_nonblock
may raise any error corresponding to recvfrom(2) failure, including Errno::EWOULDBLOCK.
If the exception is Errno::EWOULDBLOCK or Errno::EAGAIN, it is extended by IO::WaitReadable
. So IO::WaitReadable
can be used to rescue the exceptions for retrying recvfrom_nonblock.
By specifying a keyword argument exception to false
, you can indicate that recvfrom_nonblock
should not raise an IO::WaitReadable
exception, but return the symbol :wait_readable
instead.
Returns the methods available to this delegate object as the union of this object’s and _getobj_ protected methods.
Hadamard product
Matrix[[1,2], [3,4]].hadamard_product(Matrix[[1,2], [3,2]]) => 1 4 9 8
Returns the inner product of this vector with the other.
Vector[4,7].inner_product Vector[10,1] => 47
Program name to be emitted in error message and default banner, defaults to $0.
Returns the number of malloc() allocations.
Only available if ruby was built with CALC_EXACT_MALLOC_SIZE
.
Creates an HTTP
proxy class which behaves like Net::HTTP
, but performs all access via the specified proxy.
This class is obsolete. You may pass these same parameters directly to Net::HTTP.new
. See Net::HTTP.new
for details of the arguments.
True if requests for this connection will be proxied
Sends a PROPPATCH request to the path
and gets a response, as an HTTPResponse
object.
Sends a PROPFIND request to the path
and gets a response, as an HTTPResponse
object.
Advertises this service on the primary remote TupleSpace
.
True if the proxy for this connection is determined from the environment
Change the current process’s real and effective user ID to that specified by user. Returns the new user ID. Not available on all platforms.
[Process.uid, Process.euid] #=> [0, 0] Process::UID.change_privilege(31) #=> 31 [Process.uid, Process.euid] #=> [31, 31]
Set
the effective user ID, and if possible, the saved user ID of the process to the given user. Returns the new effective user ID. Not available on all platforms.
[Process.uid, Process.euid] #=> [0, 0] Process::UID.grant_privilege(31) #=> 31 [Process.uid, Process.euid] #=> [0, 31]
Get the user ID by the name. If the user is not found, ArgumentError
will be raised.
Process::UID.from_name("root") #=> 0 Process::UID.from_name("nosuchuser") #=> can't find user for nosuchuser (ArgumentError)
Change the current process’s real and effective group ID to that specified by group. Returns the new group ID. Not available on all platforms.
[Process.gid, Process.egid] #=> [0, 0] Process::GID.change_privilege(33) #=> 33 [Process.gid, Process.egid] #=> [33, 33]