Same as IO.
The line number of the last row read from this file.
Specify line number of the last row read from this file.
Resets the position of the file pointer to the point created the GzipReader object. The associated IO object needs to respond to the seek method.
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 the number of hard links to stat.
File.stat("testfile").nlink #=> 1 File.link("testfile", "testfile.bak") #=> 0 File.stat("testfile").nlink #=> 2
Produce a nicely formatted description of stat.
File.stat("/etc/passwd").inspect #=> "#<File::Stat dev=0xe000005, ino=1078078, mode=0100644, # nlink=1, uid=0, gid=0, rdev=0x0, size=1374, blksize=4096, # blocks=8, atime=Wed Dec 10 10:16:12 CST 2003, # mtime=Fri Sep 12 15:41:41 CDT 2003, # ctime=Mon Oct 27 11:20:27 CST 2003, # birthtime=Mon Aug 04 08:13:49 CDT 2003>"
Returns true if stat is writable by the effective user id of this process.
File.stat("testfile").writable? #=> true
Returns true if stat is a symbolic link, false if it isn’t or if the operating system doesn’t support this feature. As File::stat automatically follows symbolic links, symlink? will always be false for an object returned by File::stat.
File.symlink("testfile", "alink") #=> 0 File.stat("alink").symlink? #=> false File.lstat("alink").symlink? #=> 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
Inspect the buffer and report useful information about it’s internal state. Only a limited portion of the buffer will be displayed in a hexdump style format.
buffer = IO::Buffer.for("Hello World") puts buffer.inspect # #<IO::Buffer 0x000000010198ccd8+11 EXTERNAL READONLY SLICE> # 0x00000000 48 65 6c 6c 6f 20 57 6f 72 6c 64 Hello World
Transfers ownership of the underlying memory to a new buffer, causing the current buffer to become uninitialized.
buffer = IO::Buffer.new('test') other = buffer.transfer other # => # #<IO::Buffer 0x00007f136a15f7b0+4 SLICE> # 0x00000000 74 65 73 74 test buffer # => # #<IO::Buffer 0x0000000000000000+0 NULL> buffer.null? # => true
If the buffer is internal, meaning it references memory allocated by the buffer itself.
An internal buffer is not associated with any external memory (e.g. string) or file mapping.
Internal buffers are created using ::new and is the default when the requested size is less than the IO::Buffer::PAGE_SIZE and it was not requested to be mapped on creation.
Internal buffers can be resized, and such an operation will typically invalidate all slices, but not always.
If the buffer is private, meaning modifications to the buffer will not be replicated to the underlying file mapping.
# Create a test file: File.write('test.txt', 'test') # Create a private mapping from the given file. Note that the file here # is opened in read-only mode, but it doesn't matter due to the private # mapping: buffer = IO::Buffer.map(File.open('test.txt'), nil, 0, IO::Buffer::PRIVATE) # => #<IO::Buffer 0x00007fce63f11000+4 MAPPED PRIVATE> # Write to the buffer (invoking CoW of the underlying file buffer): buffer.set_string('b', 0) # => 1 # The file itself is not modified: File.read('test.txt') # => "test"
Write at least length bytes from the buffer starting at offset, into the io. 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 write operation will occur.
If offset is not given, it defaults to zero, i.e. the beginning of the buffer.
out = File.open('output.txt', 'wb') IO::Buffer.for('1234567').write(out, 3)
This leads to 123 being written into output.txt
Write at least length bytes from the buffer starting at offset, into the io starting at the specified from position. 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 pwrite operation will occur.
If offset is not given, it defaults to zero, i.e. the beginning of the buffer.
If the from position is beyond the end of the file, the gap will be filled with null (0 value) bytes.
out = File.open('output.txt', File::RDWR) # open for read/write, no truncation IO::Buffer.for('1234567').pwrite(out, 2, 3, 1)
This leads to 234 (3 bytes, starting from position 1) being written into output.txt, starting from file position 2.
Returns a human-readable string representation of this instruction sequence, including the label and path.
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 a string representation of self:
Net::HTTP.new(hostname).inspect # => "#<Net::HTTP jsonplaceholder.typicode.com:80 open=false>"
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