/*****************************************************\
* LESS    Written by: Bruce Lowther [71520,2165]      *
*                                                     *
* type <filename> | less <scoll length>               *
*                                                     *
* Less is similar to More in MS-dos, but the scroll   *
* length can be changed by entering the prefered      *
* scroll length on the command line.                  *
*                                                     *
* Example:        c:\>type less.c | less 10           *
*                                                     *
* This program is an example of combinations of       *
* the stdin stream, CON stream, and command line      *
* parameters.  If you use this program, or find it    *
* useful then yell "Thanks!" real loud, or drop me    *
* mail.  I would also like some constructive crit.,   *
* if you have any.                                    *
\*****************************************************/

#include <stdio.h>	/* for fopen(), getchar() and getc() */
#include <stdlib.h>	/* for atoi() */
#define SMALL 15		/* value of scroll if none is specified */

main (int argc,char *argv[])				/* gets the command line parameters */
{
	FILE *kbd;									/* file used when CON is opened	*/
	int counter = 1,							/* the line number counter			*/
		 letter,									/* character from stdin				*/
		 len;										/* scroll length						*/


	if (argc == 1)								/* if no command line parameter,
														set to standard scroll        */
		len = SMALL;
	else											/* else, take command line,
														convert it to integer and use
														it                            */
		len = atoi(argv[1]);

	while ((letter = getchar()) != EOF) /* loop until EOF on stdin.      */
	{
		if (counter >= len)					/* if counter has reached len,
														then stop, and get input from
														the CON (keyboard)				*/
		{
			printf("\n%d[LESS]", len);
			kbd = fopen("CON","r");			/* open the CON, for read only
														note that stdin has not been
														closed.								*/
			getc(kbd);							/* get a character from the
														keyboard								*/
			fclose (kbd);						/* close keyboard so input can
														come from stdin once again.	*/
			counter = 1;
		}
		if (letter == '\n') counter++;	/* increment counter at each
														newline character '\n'			*/
		putchar(letter);						/* put the next character onto
														stdout.								*/
	}
}