scan4.c

/*
 * simple program using scanf to read an integer
 * done right another way
 *
 * Matt Bishop, ECS 36A
 *
 * April 22, 2024
 *      first version
 */
#include <stdio.h>

/*
 * the program
 */
int main(void)
{
        int n;  	/* what is read */
	char buf[10];	/* input buffer */

        /* try to read an integer, looping until you do */

#include <stdio.h>

int main(void)
{
	int n;

	/* read a line, looping until you break or read EOF */
	while (fgets(buf, 10, stdin) != NULL){
		/* not EOF -- *now* get the integer, if any */
		if (sscanf(buf, "%d", &n) != 1){
			/* you didn't; report an error */
			fprintf(stderr, "Enter a positive integer\n");
		}
		else{
			/* you got it; print it and drop out of the loop */
			printf("I read %d\n", n);
			break;
		}
	}

	/* phew, all done! */
	return(0);
}

Matt Bishop Office: 2209 Watershed Sciences Phone: +1 (530) 752-8060 Email: mabishop@ucdavis.edu

ECS 36A, Programming & Problem Solving Version of April 2, 2024 at 12:13PM

You can get the raw source code here.