Updates modification times (mtime) and access times (atime) of the entries given by the paths in list (a single path or an array of paths); returns list if it is an array, [list] otherwise.
By default, creates an empty file for any path to a non-existent entry; use keyword argument nocreate to raise an exception instead.
Argument list or its elements should be interpretable as paths.
Examples:
# Single path. f = File.new('src0.txt') # Existing file. f.atime # => 2022-06-10 11:11:21.200277 -0700 f.mtime # => 2022-06-10 11:11:21.200277 -0700 FileUtils.touch('src0.txt') f = File.new('src0.txt') f.atime # => 2022-06-11 08:28:09.8185343 -0700 f.mtime # => 2022-06-11 08:28:09.8185343 -0700 # Array of paths. FileUtils.touch(['src0.txt', 'src0.dat'])
Keyword arguments:
mtime: time - sets the entry’s mtime to the given time, instead of the current time.
nocreate: true - raises an exception if the entry does not exist.
noop: true - does not touch entries; returns nil.
verbose: true - prints an equivalent command:
FileUtils.touch('src0.txt', noop: true, verbose: true) FileUtils.touch(['src0.txt', 'src0.dat'], noop: true, verbose: true) FileUtils.touch(path, noop: true, verbose: true)
Output:
touch src0.txt touch src0.txt src0.dat touch src0.txt
Related: FileUtils.uptodate?.
Returns an array of the string names of FileUtils methods that accept one or more keyword arguments:
FileUtils.commands.sort.take(3) # => ["cd", "chdir", "chmod"]
Set the changed state of this object. Notifications will be sent only if the changed state is true.
state
Boolean indicating the changed state of this Observable.
Returns true if this object’s state has been changed since the last notify_observers call.
Returns the arc tangent of y and x in radians.
Domain of y: [-INFINITY, INFINITY].
Domain of x: [-INFINITY, INFINITY].
Range: [-PI, PI].
Examples:
atan2(-1.0, -1.0) # => -2.356194490192345 # -3*PI/4 atan2(-1.0, 0.0) # => -1.5707963267948966 # -PI/2 atan2(-1.0, 1.0) # => -0.7853981633974483 # -PI/4 atan2(0.0, -1.0) # => 3.141592653589793 # PI
Returns the arc tangent of x.
Domain: [-INFINITY, INFINITY].
Range: [-PI/2, PI/2] .
Examples:
atan(-INFINITY) # => -1.5707963267948966 # -PI2 atan(-PI) # => -1.2626272556789115 atan(-PI/2) # => -1.0038848218538872 atan(0.0) # => 0.0 atan(PI/2) # => 1.0038848218538872 atan(PI) # => 1.2626272556789115 atan(INFINITY) # => 1.5707963267948966 # PI/2
Returns the inverse hyperbolic tangent of x.
Domain: [-1, 1].
Range: [-INFINITY, INFINITY].
Examples:
atanh(-1.0) # => -Infinity atanh(0.0) # => 0.0 atanh(1.0) # => Infinity
Returns the value of the gamma function for x.
Domain: (-INFINITY, INFINITY] excluding negative integers.
Range: [-INFINITY, INFINITY].
Examples:
gamma(-2.5) # => -0.9453087204829431 gamma(-1.5) # => 2.3632718012073513 gamma(-0.5) # => -3.5449077018110375 gamma(0.0) # => Infinity gamma(1.0) # => 1.0 gamma(2.0) # => 1.0 gamma(3.0) # => 2.0 gamma(4.0) # => 6.0 gamma(5.0) # => 24.0
Related: Math.lgamma.
Returns a 2-element array equivalent to:
[Math.log(Math.gamma(x).abs), Math.gamma(x) < 0 ? -1 : 1]
See logarithmic gamma function.
Domain: (-INFINITY, INFINITY].
Range of first element: (-INFINITY, INFINITY].
Second element is -1 or 1.
Examples:
lgamma(-4.0) # => [Infinity, -1] lgamma(-3.0) # => [Infinity, -1] lgamma(-2.0) # => [Infinity, -1] lgamma(-1.0) # => [Infinity, -1] lgamma(0.0) # => [Infinity, 1] lgamma(1.0) # => [0.0, 1] lgamma(2.0) # => [0.0, 1] lgamma(3.0) # => [0.6931471805599436, 1] lgamma(4.0) # => [1.7917594692280545, 1] lgamma(-2.5) # => [-0.05624371649767279, -1] lgamma(-1.5) # => [0.8600470153764797, 1] lgamma(-0.5) # => [1.265512123484647, -1] lgamma(0.5) # => [0.5723649429247004, 1] lgamma(1.5) # => [-0.12078223763524676, 1] lgamma(2.5) # => [0.2846828704729205, 1]
Related: Math.gamma.
Avoids the potential for a child process to become a zombie process. Process.detach prevents this by setting up a separate Ruby thread whose sole job is to reap the status of the process pid when it terminates.
This method is needed only when the parent process will never wait for the child process.
This example does not reap the second child process; that process appears as a zombie in the process status (ps) output:
pid = Process.spawn('ruby', '-e', 'exit 13') # => 312691 sleep(1) # Find zombies. system("ps -ho pid,state -p #{pid}")
Output:
312716 Z
This example also does not reap the second child process, but it does detach the process so that it does not become a zombie:
pid = Process.spawn('ruby', '-e', 'exit 13') # => 313213 thread = Process.detach(pid) sleep(1) # => #<Process::Waiter:0x00007f038f48b838 run> system("ps -ho pid,state -p #{pid}") # Finds no zombies.
The waiting thread can return the pid of the detached child process:
thread.join.pid # => 313262
Returns the maximum number of group IDs allowed in the supplemental group access list:
Process.maxgroups # => 32
Sets the maximum number of group IDs allowed in the supplemental group access list.
Dispatch enter and leave events for AlternationPatternNode nodes and continue walking the tree.
in foo | bar
Enumerates the outdated local gems yielding the local specification and the latest remote version.
This method may take some time to return as it must check each local gem against the server’s index.
Returns a Hash containing the following keys:
Number of started SSL/TLS handshakes in server mode
Number of established SSL/TLS sessions in server mode
Number of start renegotiations in server mode
Number of sessions that were removed due to cache overflow
Number of successfully reused connections
Number of sessions proposed by clients that were not found in the cache
Number of sessions in the internal session cache
Number of sessions retrieved from the external cache in server mode
Number of started SSL/TLS handshakes in client mode
Number of established SSL/TLS sessions in client mode
Number of start renegotiations in client mode
Number of sessions proposed by clients that were found in the cache but had expired due to timeouts
Enables use of shared session key material in accordance with RFC 5705.