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Filename : map-c.ri
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U:RDoc::AnyMethod[iI"map:ETI"IO::Buffer::map;TT:publico:RDoc::Markup::Document:@parts[
o:RDoc::Markup::Paragraph;	[I"NCreate an IO::Buffer for reading from +file+ by memory-mapping the file. ;TI"?+file_io+ should be a +File+ instance, opened for reading.;To:RDoc::Markup::BlankLine�o;
;	[I">Optional +size+ and +offset+ of mapping can be specified.;T@o;
;	[I"QBy default, the buffer would be immutable (read only); to create a writable ;TI"Nmapping, you need to open a file in read-write mode, and explicitly pass ;TI"4+flags+ argument without IO::Buffer::IMMUTABLE.;T@o:RDoc::Markup::Verbatim;	[I"$File.write('test.txt', 'test')
;TI"
;TI"Rbuffer = IO::Buffer.map(File.open('test.txt'), nil, 0, IO::Buffer::READONLY)
;TI"=# => #<IO::Buffer 0x00000001014a0000+4 MAPPED READONLY>
;TI"
;TI""buffer.readonly?   # => true
;TI"
;TI"buffer.get_string
;TI"# => "test"
;TI"
;TI"buffer.set_string('b', 0)
;TI"G# `set_string': Buffer is not writable! (IO::Buffer::AccessError)
;TI"
;TI"D# create read/write mapping: length 4 bytes, offset 0, flags 0
;TI"@buffer = IO::Buffer.map(File.open('test.txt', 'r+'), 4, 0)
;TI"buffer.set_string('b', 0)
;TI"# => 1
;TI"
;TI"# Check it
;TI"File.read('test.txt')
;TI"# => "best"
;T:@format0o;
;	[I"RNote that some operating systems may not have cache coherency between mapped ;TI"buffers and file reads.;T:
@fileI"io_buffer.c;T:0@omit_headings_from_table_of_contents_below0I"BIO::Buffer.map(file, [size, [offset, [flags]]]) -> io_buffer
;T0[�I"(*args);T@3FI"Buffer;TcRDoc::NormalClass00