Computes the sine of x
(expressed in radians). Returns a Float
in the range -1.0..1.0.
Domain: (-INFINITY, INFINITY)
Codomain: [-1, 1]
Math.sin(Math::PI/2) #=> 1.0
Computes the arc sine of x
. Returns -PI/2..PI/2.
Domain: [-1, -1]
Codomain: [-PI/2, PI/2]
Math.asin(1) == Math::PI/2 #=> true
Computes the hyperbolic sine of x
(expressed in radians).
Domain: (-INFINITY, INFINITY)
Codomain: (-INFINITY, INFINITY)
Math.sinh(0) #=> 0.0
Computes the inverse hyperbolic sine of x
.
Domain: (-INFINITY, INFINITY)
Codomain: (-INFINITY, INFINITY)
Math.asinh(1) #=> 0.881373587019543
Gets the resource limit of the process. cur_limit means current (soft) limit and max_limit means maximum (hard) limit.
resource indicates the kind of resource to limit. It is specified as a symbol such as :CORE
, a string such as "CORE"
or a constant such as Process::RLIMIT_CORE
. See Process.setrlimit
for details.
cur_limit and max_limit may be Process::RLIM_INFINITY
, Process::RLIM_SAVED_MAX
or Process::RLIM_SAVED_CUR
. See Process.setrlimit
and the system getrlimit(2) manual for details.
Sets the resource limit of the process. cur_limit means current (soft) limit and max_limit means maximum (hard) limit.
If max_limit is not given, cur_limit is used.
resource indicates the kind of resource to limit. It should be a symbol such as :CORE
, a string such as "CORE"
or a constant such as Process::RLIMIT_CORE
. The available resources are OS dependent. Ruby may support following resources.
total available memory (bytes) (SUSv3, NetBSD, FreeBSD, OpenBSD but 4.4BSD-Lite)
core size (bytes) (SUSv3)
CPU time (seconds) (SUSv3)
data segment (bytes) (SUSv3)
file size (bytes) (SUSv3)
total size for mlock(2) (bytes) (4.4BSD, GNU/Linux)
allocation for POSIX message queues (bytes) (GNU/Linux)
ceiling on process’s nice(2) value (number) (GNU/Linux)
file descriptors (number) (SUSv3)
number of processes for the user (number) (4.4BSD, GNU/Linux)
RSS
resident memory size (bytes) (4.2BSD, GNU/Linux)
ceiling on the process’s real-time priority (number) (GNU/Linux)
CPU time for real-time process (us) (GNU/Linux)
all socket buffers (bytes) (NetBSD, FreeBSD)
number of queued signals allowed (signals) (GNU/Linux)
stack size (bytes) (SUSv3)
cur_limit and max_limit may be :INFINITY
, "INFINITY"
or Process::RLIM_INFINITY
, which means that the resource is not limited. They may be Process::RLIM_SAVED_MAX
, Process::RLIM_SAVED_CUR
and corresponding symbols and strings too. See system setrlimit(2) manual for details.
The following example raises the soft limit of core size to the hard limit to try to make core dump possible.
Process.setrlimit(:CORE, Process.getrlimit(:CORE)[1])
Initializes the supplemental group access list by reading the system group database and using all groups of which the given user is a member. The group with the specified gid is also added to the list. Returns the resulting Array
of the gids of all the groups in the supplementary group access list. Not available on all platforms.
Process.groups #=> [0, 1, 2, 3, 4, 6, 10, 11, 20, 26, 27] Process.initgroups( "mgranger", 30 ) #=> [30, 6, 10, 11] Process.groups #=> [30, 6, 10, 11]
Specifies the handling of signals. The first parameter is a signal name (a string such as “SIGALRM”, “SIGUSR1”, and so on) or a signal number. The characters “SIG” may be omitted from the signal name. The command or block specifies code to be run when the signal is raised. If the command is the string “IGNORE” or “SIG_IGN”, the signal will be ignored. If the command is “DEFAULT” or “SIG_DFL”, the Ruby’s default handler will be invoked. If the command is “EXIT”, the script will be terminated by the signal. If the command is “SYSTEM_DEFAULT”, the operating system’s default handler will be invoked. Otherwise, the given command or block will be run. The special signal name “EXIT” or signal number zero will be invoked just prior to program termination. trap returns the previous handler for the given signal.
Signal.trap(0, proc { puts "Terminating: #{$$}" }) Signal.trap("CLD") { puts "Child died" } fork && Process.wait
produces:
Terminating: 27461 Child died Terminating: 27460
Returns a list of signal names mapped to the corresponding underlying signal numbers.
Signal.list #=> {"EXIT"=>0, "HUP"=>1, "INT"=>2, "QUIT"=>3, "ILL"=>4, "TRAP"=>5, "IOT"=>6, "ABRT"=>6, "FPE"=>8, "KILL"=>9, "BUS"=>7, "SEGV"=>11, "SYS"=>31, "PIPE"=>13, "ALRM"=>14, "TERM"=>15, "URG"=>23, "STOP"=>19, "TSTP"=>20, "CONT"=>18, "CHLD"=>17, "CLD"=>17, "TTIN"=>21, "TTOU"=>22, "IO"=>29, "XCPU"=>24, "XFSZ"=>25, "VTALRM"=>26, "PROF"=>27, "WINCH"=>28, "USR1"=>10, "USR2"=>12, "PWR"=>30, "POLL"=>29}
Return the best specification that contains the file matching path
amongst the specs that are not activated.
State
Transition Table Serialization
Iterates through the child elements, yielding for each Element
that has a particular attribute set.
the name of the attribute to search for
the value of the attribute
(optional) causes this method to return after yielding for this number of matching children
(optional) if supplied, this is an XPath
that filters the children to check.
doc = Document.new "<a><b @id='1'/><c @id='2'/><d @id='1'/><e/></a>" # Yields b, c, d doc.root.each_element_with_attribute( 'id' ) {|e| p e} # Yields b, d doc.root.each_element_with_attribute( 'id', '1' ) {|e| p e} # Yields b doc.root.each_element_with_attribute( 'id', '1', 1 ) {|e| p e} # Yields d doc.root.each_element_with_attribute( 'id', '1', 0, 'd' ) {|e| p e}
Writes the file containing the arguments for building this gem’s extensions.
Creates the following instance variables:
a spec named ‘a’, intended for regular installs
a spec named ‘b’, intended for user installs
the path to a built gem from @spec
the path to a built gem from @user_spec
And returns a Gem::Installer
for the @user_spec that installs into Gem.user_dir
Add the install/update options to the option parser.