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Scanf.Scanning(3)		   OCamldoc		     Scanf.Scanning(3)

NAME
       Scanf.Scanning -	no description

Module
       Module	Scanf.Scanning

Documentation
       Module Scanning
	: sig end

       type in_channel

       The  notion  of input channel for the Scanf module: those channels pro-
       vide all	the machinery necessary	to read	from any source	of characters,
       including  a  Pervasives.in_channel value.  A Scanf.Scanning.in_channel
       value is	also called a formatted	input channel or equivalently a	 scan-
       ning  buffer.   The  type  Scanf.Scanning.scanbuf below is an alias for
       Scanning.in_channel .

       Since 3.12.0

       type scanbuf = in_channel

       The type	of scanning buffers. A scanning	 buffer	 is  the  source  from
       which  a	 formatted input function gets characters. The scanning	buffer
       holds the current state of the scan, plus a function to	get  the  next
       char  from the input, and a token buffer	to store the string matched so
       far.

       Note: a scanning	action may often require to examine one	 character  in
       advance;	 when  this 'lookahead'	character does not belong to the token
       read, it	is stored back in the scanning buffer  and  becomes  the  next
       character yet to	be read.

       val stdin : in_channel

       The  standard input notion for the Scanf	module.	 Scanning.stdin	is the
       Scanf.Scanning.in_channel formatted input channel  attached  to	Perva-
       sives.stdin .

       Note:  in  the  interactive  system,  when  input  is  read from	Perva-
       sives.stdin , the newline character that	triggers evaluation is part of
       the  input;  thus,  the scanning	specifications must properly skip this
       additional newline character (for instance, simply add a	 '\n'  as  the
       last character of the format string).

       Since 3.12.0

       type file_name =	string

       A convenient alias to designate a file name.

       Since 4.00.0

       val open_in : file_name -> in_channel

       Scanning.open_in	 fname	returns	 a Scanf.Scanning.in_channel formatted
       input channel for bufferized reading in text mode from file fname .

       Note: open_in returns a formatted input channel that efficiently	 reads
       characters  in  large  chunks;  in contrast, from_channel below returns
       formatted input channels	that must read one character at	a time,	 lead-
       ing to a	much slower scanning rate.

       Since 3.12.0

       val open_in_bin : file_name -> in_channel

       Scanning.open_in_bin  fname returns a Scanf.Scanning.in_channel format-
       ted input channel for bufferized	reading	in binary mode from file fname
       .

       Since 3.12.0

       val close_in : in_channel -> unit

       Closes  the Pervasives.in_channel associated with the given Scanf.Scan-
       ning.in_channel formatted input channel.

       Since 3.12.0

       val from_file : file_name -> in_channel

       An alias	for Scanf.Scanning.open_in above.

       val from_file_bin : string -> in_channel

       An alias	for Scanf.Scanning.open_in_bin above.

       val from_string : string	-> in_channel

       Scanning.from_string s returns  a  Scanf.Scanning.in_channel  formatted
       input  channel  which reads from	the given string.  Reading starts from
       the first character in the string.  The end-of-input condition  is  set
       when the	end of the string is reached.

       val from_function : (unit -> char) -> in_channel

       Scanning.from_function  f returns a Scanf.Scanning.in_channel formatted
       input channel with the given function as	its reading method.

       When scanning needs one more character, the given function is called.

       When the	function has no	more character to provide, it must  signal  an
       end-of-input condition by raising the exception End_of_file .

       val from_channel	: Pervasives.in_channel	-> in_channel

       Scanning.from_channel  ic returns a Scanf.Scanning.in_channel formatted
       input channel which reads from the regular Pervasives.in_channel	 input
       channel	ic argument.  Reading starts at	current	reading	position of ic
       .

       val end_of_input	: in_channel ->	bool

       Scanning.end_of_input ic	tests the end-of-input condition of the	 given
       Scanf.Scanning.in_channel formatted input channel.

       val beginning_of_input :	in_channel -> bool

       Scanning.beginning_of_input  ic	tests the beginning of input condition
       of the given Scanf.Scanning.in_channel formatted	input channel.

       val name_of_input : in_channel -> string

       Scanning.name_of_input ic returns the name of the character source  for
       the given Scanf.Scanning.in_channel formatted input channel.

       Since 3.09.0

       val stdib : in_channel

       A deprecated alias for Scanf.Scanning.stdin , the scanning buffer read-
       ing from	Pervasives.stdin .

2020-08-11			    source:		     Scanf.Scanning(3)

NAME | Module | Documentation

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