Thread: Reading in an int followed by a string

Why is it that the following code:

printf("? ");
scanf("%d", &n);
printf("? ");
gets(str);

skip the gets(str) step?

My guess is that the carriage return is not stored into n and still in the stdin, so that when gets(str) is called, the carriage return is encountered. Am I correct?

Is there anyway to solve this anomaly besides switching the positions of the code or use gets() and atoi?

I believe you are correct, the CR has not been read yet and carries into the second read.

Add after the first read a call to flush the input buffer:
fflush(stdin);

That should do it for you.

Walt

Originally posted by Salem
Someone else needs to read the FAQ as well then
http://faq.cprogramming.com/cgi-bin/...&id=1043284392

The FAQ does state for the C standard fflush(stdin); behavior is undefined but it also states As usual, there are some exceptions, check your compiler's documentation. The original question was

Why is it that the following code:
. . .
skip the gets(str) step?

not is there a better way which the response from Salem answered.

In Borland, fflush(stdin) works as early as Turbo 1.0. If they removed it's funtionality, I am unaware of it, although I doubt it.

Maybe a better answer using scanf would be
sscanf("%d%c", &num, &dummy);
with the %c to read off the CR, but the typed in character string is critical. It in fact would be better to use fgets() routine as implied. I personally dislike scanf() because of its ideosyncracies.

Walt