Reads at most maxlen bytes from the gzipped stream but it blocks only if gzipreader has no data immediately available. If the optional outbuf argument is present, it must reference a String, which will receive the data. It raises EOFError on end of file.
See Zlib::GzipReader documentation for a description.
See Zlib::GzipReader documentation for a description.
See Zlib::GzipReader documentation for a description.
See Zlib::GzipReader documentation for a description.
Returns true if stat is readable by the effective user id of this process.
File.stat("testfile").readable? #=> true
Returns true if stat has its sticky bit set, false if it doesn’t or if the operating system doesn’t support this feature.
File.stat("testfile").sticky? #=> false
Creates a zero-copy IO::Buffer from the given string’s memory. Without a block a frozen internal copy of the string is created efficiently and used as the buffer source. When a block is provided, the buffer is associated directly with the string’s internal buffer and updating the buffer will update the string.
Until free is invoked on the buffer, either explicitly or via the garbage collector, the source string will be locked and cannot be modified.
If the string is frozen, it will create a read-only buffer which cannot be modified. If the string is shared, it may trigger a copy-on-write when using the block form.
string = 'test' buffer = IO::Buffer.for(string) buffer.external? #=> true buffer.get_string(0, 1) # => "t" string # => "best" buffer.resize(100) # in `resize': Cannot resize external buffer! (IO::Buffer::AccessError) IO::Buffer.for(string) do |buffer| buffer.set_string("T") string # => "Test" end
Creates a new string of the given length and yields a zero-copy IO::Buffer instance to the block which uses the string as a source. The block is expected to write to the buffer and the string will be returned.
IO::Buffer.string(4) do |buffer| buffer.set_string("Ruby") end # => "Ruby"
Short representation of the buffer. It includes the address, size and symbolic flags. This format is subject to change.
puts IO::Buffer.new(4) # uses to_s internally # #<IO::Buffer 0x000055769f41b1a0+4 INTERNAL>
If the buffer is shared, meaning it references memory that can be shared with other processes (and thus might change without being modified locally).
# Create a test file: File.write('test.txt', 'test') # Create a shared mapping from the given file, the file must be opened in # read-write mode unless we also specify IO::Buffer::READONLY: buffer = IO::Buffer.map(File.open('test.txt', 'r+'), nil, 0) # => #<IO::Buffer 0x00007f1bffd5e000+4 EXTERNAL MAPPED SHARED> # Write to the buffer, which will modify the mapped file: buffer.set_string('b', 0) # => 1 # The file itself is modified: File.read('test.txt') # => "best"
If the buffer is read only, meaning the buffer cannot be modified using set_value, set_string or copy and similar.
Frozen strings and read-only files create read-only buffers.
Resizes a buffer to a new_size bytes, preserving its content. Depending on the old and new size, the memory area associated with the buffer might be either extended, or rellocated at different address with content being copied.
buffer = IO::Buffer.new(4) buffer.set_string("test", 0) buffer.resize(8) # resize to 8 bytes # => # #<IO::Buffer 0x0000555f5d1a1630+8 INTERNAL> # 0x00000000 74 65 73 74 00 00 00 00 test....
External buffer (created with ::for), and locked buffer can not be resized.
If the buffer references memory, release it back to the operating system.
for a mapped buffer (e.g. from file): unmap.
for a buffer created from scratch: free memory.
for a buffer created from string: undo the association.
After the buffer is freed, no further operations can’t be performed on it.
You can resize a freed buffer to re-allocate it.
buffer = IO::Buffer.for('test') buffer.free # => #<IO::Buffer 0x0000000000000000+0 NULL> buffer.get_value(:U8, 0) # in `get_value': The buffer is not allocated! (IO::Buffer::AllocationError) buffer.get_string # in `get_string': The buffer is not allocated! (IO::Buffer::AllocationError) buffer.null? # => true
Modify the source buffer in place by applying the binary OR operation to the source, using the mask, repeating as necessary.
source = IO::Buffer.for("1234567890").dup # Make a read/write copy. # => # #<IO::Buffer 0x000056307a272350+10 INTERNAL> # 0x00000000 31 32 33 34 35 36 37 38 39 30 1234567890 source.or!(IO::Buffer.for("\xFF\x00\x00\xFF")) # => # #<IO::Buffer 0x000056307a272350+10 INTERNAL> # 0x00000000 ff 32 33 ff ff 36 37 ff ff 30 .23..67..0
Modify the source buffer in place by applying the binary XOR operation to the source, using the mask, repeating as necessary.
source = IO::Buffer.for("1234567890").dup # Make a read/write copy. # => # #<IO::Buffer 0x000056307a25b3e0+10 INTERNAL> # 0x00000000 31 32 33 34 35 36 37 38 39 30 1234567890 source.xor!(IO::Buffer.for("\xFF\x00\x00\xFF")) # => # #<IO::Buffer 0x000056307a25b3e0+10 INTERNAL> # 0x00000000 ce 32 33 cb ca 36 37 c7 c6 30 .23..67..0
Read at least length bytes from the io, into the buffer starting at offset. If an error occurs, return -errno.
If length is not given or nil, it defaults to the size of the buffer minus the offset, i.e. the entire buffer.
If length is zero, exactly one read operation will occur.
If offset is not given, it defaults to zero, i.e. the beginning of the buffer.
IO::Buffer.for('test') do |buffer| p buffer # => # <IO::Buffer 0x00007fca40087c38+4 SLICE> # 0x00000000 74 65 73 74 test buffer.read(File.open('/dev/urandom', 'rb'), 2) p buffer # => # <IO::Buffer 0x00007f3bc65f2a58+4 EXTERNAL SLICE> # 0x00000000 05 35 73 74 .5st end
Read at least length bytes from the io starting at the specified from position, into the buffer starting at offset. If an error occurs, return -errno.
If length is not given or nil, it defaults to the size of the buffer minus the offset, i.e. the entire buffer.
If length is zero, exactly one pread operation will occur.
If offset is not given, it defaults to zero, i.e. the beginning of the buffer.
IO::Buffer.for('test') do |buffer| p buffer # => # <IO::Buffer 0x00007fca40087c38+4 SLICE> # 0x00000000 74 65 73 74 test # take 2 bytes from the beginning of urandom, # put them in buffer starting from position 2 buffer.pread(File.open('/dev/urandom', 'rb'), 0, 2, 2) p buffer # => # <IO::Buffer 0x00007f3bc65f2a58+4 EXTERNAL SLICE> # 0x00000000 05 35 73 74 te.5 end
Returns an Array with 14 elements representing the instruction sequence with the following data:
A string identifying the data format. Always YARVInstructionSequence/SimpleDataFormat.
The major version of the instruction sequence.
The minor version of the instruction sequence.
A number identifying the data format. Always 1.
A hash containing:
:arg_sizethe total number of arguments taken by the method or the block (0 if iseq doesn’t represent a method or block)
:local_sizethe number of local variables + 1
:stack_maxused in calculating the stack depth at which a SystemStackError is thrown.
labelThe name of the context (block, method, class, module, etc.) that this instruction sequence belongs to.
<main> if it’s at the top level, <compiled> if it was evaluated from a string.
pathThe relative path to the Ruby file where the instruction sequence was loaded from.
<compiled> if the iseq was evaluated from a string.
absolute_pathThe absolute path to the Ruby file where the instruction sequence was loaded from.
nil if the iseq was evaluated from a string.
first_linenoThe number of the first source line where the instruction sequence was loaded from.
The type of the instruction sequence.
Valid values are :top, :method, :block, :class, :rescue, :ensure, :eval, :main, and plain.
An array containing the names of all arguments and local variables as symbols.
An Hash object containing parameter information.
More info about these values can be found in vm_core.h.
A list of exceptions and control flow operators (rescue, next, redo, break, etc.).
An array of arrays containing the instruction names and operands that make up the body of the instruction sequence.
Note that this format is MRI specific and version dependent.
Posts data to a host; returns a Net::HTTPResponse object.
Argument url must be a URL; argument data must be a string:
_uri = uri.dup _uri.path = '/posts' data = '{"title": "foo", "body": "bar", "userId": 1}' headers = {'content-type': 'application/json'} res = Net::HTTP.post(_uri, data, headers) # => #<Net::HTTPCreated 201 Created readbody=true> puts res.body
Output:
{
"title": "foo",
"body": "bar",
"userId": 1,
"id": 101
}
Related:
Net::HTTP::Post: request class for HTTP method POST.
Net::HTTP#post: convenience method for HTTP method POST.
Creates a new Net::HTTP object, http, via Net::HTTP.new:
For arguments address and port, see Net::HTTP.new.
For proxy-defining arguments p_addr through p_pass, see Proxy Server.
For argument opts, see below.
With no block given:
Calls http.start with no block (see start), which opens a TCP connection and HTTP session.
Returns http.
The caller should call finish to close the session:
http = Net::HTTP.start(hostname) http.started? # => true http.finish http.started? # => false
With a block given:
Calls http.start with the block (see start), which:
Opens a TCP connection and HTTP session.
Calls the block, which may make any number of requests to the host.
Closes the HTTP session and TCP connection on block exit.
Returns the block’s value object.
Returns object.
Example:
hostname = 'jsonplaceholder.typicode.com' Net::HTTP.start(hostname) do |http| puts http.get('/todos/1').body puts http.get('/todos/2').body end
Output:
{
"userId": 1,
"id": 1,
"title": "delectus aut autem",
"completed": false
}
{
"userId": 1,
"id": 2,
"title": "quis ut nam facilis et officia qui",
"completed": false
}
If the last argument given is a hash, it is the opts hash, where each key is a method or accessor to be called, and its value is the value to be set.
The keys may include:
Note: If port is nil and opts[:use_ssl] is a truthy value, the value passed to new is Net::HTTP.https_default_port, not port.
Returns true if the HTTP session has been started:
http = Net::HTTP.new(hostname) http.started? # => false http.start http.started? # => true http.finish # => nil http.started? # => false Net::HTTP.start(hostname) do |http| http.started? end # => true http.started? # => false
Starts an HTTP session.
Without a block, returns self:
http = Net::HTTP.new(hostname) # => #<Net::HTTP jsonplaceholder.typicode.com:80 open=false> http.start # => #<Net::HTTP jsonplaceholder.typicode.com:80 open=true> http.started? # => true http.finish
With a block, calls the block with self, finishes the session when the block exits, and returns the block’s value:
http.start do |http| http end # => #<Net::HTTP jsonplaceholder.typicode.com:80 open=false> http.started? # => false
Sends a POST request to the server; returns an instance of a subclass of Net::HTTPResponse.
The request is based on the Net::HTTP::Post object created from string path, string data, and initial headers hash initheader.
With a block given, calls the block with the response body:
data = '{"userId": 1, "id": 1, "title": "delectus aut autem", "completed": false}' http = Net::HTTP.new(hostname) http.post('/todos', data) do |res| p res end # => #<Net::HTTPCreated 201 Created readbody=true>
Output:
"{\n \"{\\\"userId\\\": 1, \\\"id\\\": 1, \\\"title\\\": \\\"delectus aut autem\\\", \\\"completed\\\": false}\": \"\",\n \"id\": 201\n}"
With no block given, simply returns the response object:
http.post('/todos', data) # => #<Net::HTTPCreated 201 Created readbody=true>
Related:
Net::HTTP::Post: request class for HTTP method POST.
Net::HTTP.post: sends POST request, returns response body.