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std::fgets(3)		      C++ Standard Libary		 std::fgets(3)

NAME
       std::fgets - std::fgets

Synopsis
	  Defined in header <cstdio>
	  char*	fgets( char* str, int count, std::FILE*	stream );

	  Reads	 at  most  count - 1 characters	from the given file stream and
       stores them in the
	  character array pointed to by	str. Parsing stops if a	newline	 char-
       acter is	found, in
	  which	 case  str  will contain that newline character, or if end-of-
       file occurs. If
	  bytes	are read and no	errors occur, writes a null character  at  the
       position
	  immediately after the	last character written to str.

Parameters
	  str	 - pointer to an element of a char array
	  count	 - maximum number of characters	to write (typically the	length
       of str)
	  stream - file	stream to read the data	from

Return value
	  str on success, null pointer on failure.

	  If  the end-of-file condition	is encountered,	sets the eof indicator
       on stream (see
	  std::feof()).	This is	only a failure if it causes  no	 bytes	to  be
       read, in	which case
	  a  null pointer is returned and the contents of the array pointed to
       by str are not
	  altered (i.e.	the first byte is not overwritten with a null  charac-
       ter).

	  If  the  failure has been caused by some other error,	sets the error
       indicator (see
	  std::ferror()) on stream. The	contents of the	array  pointed	to  by
       str are
	  indeterminate	(it may	not even be null-terminated).

Notes
	  POSIX	additionally requires that fgets sets errno if it encounters a
       failure other
	  than the end-of-file condition.

	  Although  the	 standard  specification is unclear in the cases where
       count<=1, common
	  implementations do

	    * if count < 1, do nothing,	report error
	    * if count == 1,

		     * some implementations do nothing,	report error,
		     * others read nothing, store zero in str[0], report  suc-
       cess

Example
       // Run this code

	#include <iostream>
	#include <cstdio>
	#include <cstdlib>

	int main()
	{
	    std::FILE* tmpf = std::tmpfile();
	    std::fputs("Alan Turing\n",	tmpf);
	    std::fputs("John von Neumann\n", tmpf);
	    std::fputs("Alonzo Church\n", tmpf);

	    std::rewind(tmpf);
	    char buf[8];
	    while (std::fgets(buf, sizeof buf, tmpf) !=	nullptr) {
		std::cout << '"' << buf	<< '"' << '\n';
	    }
	}

Output:
	"Alan Tu"
	"ring
	"
	"John vo"
	"n Neuma"
	"nn
	"
	"Alonzo	"
	"Church
	"

See also
	  scanf			 reads	formatted  input  from	stdin,	a file
       stream or a buffer
	  fscanf		(function)
	  sscanf
	  gets			reads a	character string from stdin
	  (deprecated in C++11)	(function)
	  (removed in C++14)
	  fputs			writes a character string to a file stream
				(function)

http://cppreference.com		  2022.07.31			 std::fgets(3)

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