Hi
Can you help me understand with some level of detail (I guess that we overflow the stdin buffer on purpose, however the details escape me) what leads to the output of the code below for an input of "ululul" to be "ULULUL" instead of what I would expect to be "uUlLuUlLuUlL"?
Code:#include <stdio.h> #include <ctype.h> int main() { char c; printf("Insert a word [Press enter to finish]\n"); //fflush(stdin); do { scanf("%c", &c); printf("%c", toupper(c)); }while(c != '\n'); return(0); }
Last edited by euonym; 12-14-2010 at 09:01 PM.
Why would it? You'd have to use printf("%c%c", c, toupper(c));
Also, void main() is bad as well as fflush(stdin);
If you understand what you're doing, you're not learning anything.
I'm sorry about that, you are correct.
Still, can you help me understand why it doesn't process one char at a time, or why it doesn't ignore all but the last char?
But it does process one character at a time. Type any character and press enter. Then run it with a different length input. The only difference is when you press enter. Your experiment results mean that stdin is line buffered. In other words, scanf will read until a whole line is in stdin and then only return the first character. Subsequent calls to scanf will be streamed from stdin, until after the '\n' character is encountered.
Thank you for the concise explanation.
