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

NAME
     std::feof - std::feof

Synopsis
	Defined in header <cstdio>
	int feof( std::FILE* stream );

	Checks if the end of the given file stream has been reached.

Parameters
	stream - the file stream to check

Return value
	Nonzero value if the end of the stream has been reached, otherwise 0.

Notes
	This  function only reports the stream state as reported by the most re-
     cent I/O
	operation, it does not examine the associated data source. For	example,
     if the most
	recent	I/O  was  a  std::fgetc, which returned the last byte of a file,
     std::feof
	returns zero. The next std::fgetc fails and changes the stream state  to
     end-of-file.
	Only then std::feof returns non-zero.

	In  typical  usage, input stream processing stops on any error; feof and
     std::ferror
	are then used to distinguish between different error conditions.

Example
     // Run this code

      #include <cstdio>
      #include <cstdlib>

      int main()
      {
	  int is_ok = EXIT_FAILURE;
	  FILE* fp = std::fopen("/tmp/test.txt", "w+");
	  if (!fp)
	  {
	      std::perror("File opening failed");
	      return is_ok;
	  }

	  int c; // Note: int, not char, required to handle EOF
	  while ((c = std::fgetc(fp)) != EOF) // Standard  C  I/O  file  reading
     loop
	      std::putchar(c);

	  if (std::ferror(fp))
	      std::puts("I/O error when reading");
	  else if (std::feof(fp))
	  {
	      std::puts("End of file reached successfully");
	      is_ok = EXIT_SUCCESS;
	  }

	  std::fclose(fp);
	  return is_ok;
      }

Output:
      End of file reached successfully

See also
	eof	 checks if end-of-file has been reached
		 (public member function of std::basic_ios<CharT,Traits>)
	clearerr clears errors
		 (function)
	perror	  displays a character string corresponding of the current error
     to stderr
		 (function)
	ferror	 checks for a file error
		 (function)
	C documentation for
	feof

http://cppreference.com 	   2024.06.10			    std::feof(3)
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