INFO: rewind(stdin) Clears Keyboard Buffer

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Summary


To clear the keyboard buffer in Microsoft C use the function rewind() with the stream STDIN, which is associated with the keyboard by default. The function fflush() clears the buffers that C programs use for stream level I/O. It does not clear the device buffer. The following is an example that shows what happens when the keyboard buffer is not cleared, and then how to clear it:

Sample Code

/* Compile options needed: none
*/

#include <stdio.h>

void main(void)
{
int ch ;

puts( "Input two or more chars. One is read now." );
ch = getchar();
putchar( ch );
putchar( '\n' );

puts( "The next char is taken from stdin." );
ch = getchar( );
putchar( ch );
putchar( '\n' );

rewind( stdin );
puts( "Input two or more chars. One is read now." );
ch = getchar();
putchar( ch );
putchar( '\n' );

rewind( stdin );
puts( "You must enter another char because of the rewind(stdin)" );
ch = getchar( );
putchar( ch );
putchar( '\n' );
}
Properties

Article ID: 41159 - Last Review: 17-Jun-2014 - Revision: 1

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