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Filename :
readpartial-i.ri
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U:RDoc::AnyMethod[iI"readpartial:ETI"IO#readpartial;TF: publico:RDoc::Markup::Document: @parts[ o: RDoc::Markup::Paragraph; [I"1Reads up to +maxlen+ bytes from the stream; ;TI"Greturns a string (either a new string or the given +out_string+). ;TI"Its encoding is:;To: RDoc::Markup::BlankLine o:RDoc::Markup::List: @type: BULLET: @items[ o:RDoc::Markup::ListItem: @label0; [o; ; [I"FThe unchanged encoding of +out_string+, if +out_string+ is given.;To;;0; [o; ; [I"ASCII-8BIT, otherwise.;T@o;;0; [o; ; [I";Contains +maxlen+ bytes from the stream, if available.;To;;0; [o; ; [I">Otherwise contains all available bytes, if any available.;To;;0; [o; ; [I""Otherwise is an empty string.;T@o; ; [I"CWith the single non-negative integer argument +maxlen+ given, ;TI"returns a new string:;T@o:RDoc::Markup::Verbatim; [ I"f = File.new('t.txt') ;TI"3f.readpartial(20) # => "First line\nSecond l" ;TI"3f.readpartial(20) # => "ine\n\nFourth line\n" ;TI"+f.readpartial(20) # => "Fifth line\n" ;TI"*f.readpartial(20) # Raises EOFError. ;TI" f.close ;T: @format0o; ; [I"IWith both argument +maxlen+ and string argument +out_string+ given, ;TI"#returns modified +out_string+:;T@o;; [ I"f = File.new('t.txt') ;TI"s = 'foo' ;TI"6f.readpartial(20, s) # => "First line\nSecond l" ;TI"s = 'bar' ;TI""f.readpartial(0, s) # => "" ;TI" f.close ;T;0o; ; [I"LThis method is useful for a stream such as a pipe, a socket, or a tty. ;TI";It blocks only when no data is immediately available. ;TI"IThis means that it blocks only when _all_ of the following are true:;T@o; ; ;;[o;;0; [o; ; [I",The byte buffer in the stream is empty.;To;;0; [o; ; [I"(The content of the stream is empty.;To;;0; [o; ; [I" The stream is not at EOF.;T@o; ; [I"NWhen blocked, the method waits for either more data or EOF on the stream:;T@o; ; ;;[o;;0; [o; ; [I"7If more data is read, the method returns the data.;To;;0; [o; ; [I"3If EOF is reached, the method raises EOFError.;T@o; ; [I"7When not blocked, the method responds immediately:;T@o; ; ;;[o;;0; [o; ; [I"2Returns data from the buffer if there is any.;To;;0; [o; ; [I"<Otherwise returns data from the stream if there is any.;To;;0; [o; ; [I"=Otherwise raises EOFError if the stream has reached EOF.;T@o; ; [I"FNote that this method is similar to sysread. The differences are:;T@o; ; ;;[o;;0; [o; ; [I"@If the byte buffer is not empty, read from the byte buffer ;TI"4instead of "sysread for buffered IO (IOError)".;To;;0; [o; ; [I"AIt doesn't cause Errno::EWOULDBLOCK and Errno::EINTR. When ;TI"Breadpartial meets EWOULDBLOCK and EINTR by read system call, ;TI")readpartial retries the system call.;T@o; ; [I"IThe latter means that readpartial is non-blocking-flag insensitive. ;TI"HIt blocks on the situation IO#sysread causes Errno::EWOULDBLOCK as ;TI" if the fd is blocking mode.;T@o; ; [I"Examples:;T@o;; [I"M# # Returned Buffer Content Pipe Content ;TI" r, w = IO.pipe # ;TI"Gw << 'abc' # "" "abc". ;TI"Cr.readpartial(4096) # => "abc" "" "" ;TI"Lr.readpartial(4096) # (Blocks because buffer and pipe are empty.) ;TI" ;TI"M# # Returned Buffer Content Pipe Content ;TI" r, w = IO.pipe # ;TI"Fw << 'abc' # "" "abc" ;TI"Jw.close # "" "abc" EOF ;TI"Er.readpartial(4096) # => "abc" "" EOF ;TI"0r.readpartial(4096) # raises EOFError ;TI" ;TI"M# # Returned Buffer Content Pipe Content ;TI" r, w = IO.pipe # ;TI"Mw << "abc\ndef\n" # "" "abc\ndef\n" ;TI"Cr.gets # => "abc\n" "def\n" "" ;TI"Hw << "ghi\n" # "def\n" "ghi\n" ;TI"Hr.readpartial(4096) # => "def\n" "" "ghi\n" ;TI"Br.readpartial(4096) # => "ghi\n" "" "";T;0: @fileI" io.c;T:0@omit_headings_from_table_of_contents_below0I"]readpartial(maxlen) -> string readpartial(maxlen, out_string) -> out_string ;T0[ I" (*args);T@�FI"IO;TcRDoc::NormalClass00