Why scanf(“%d”, […]) does not consume ‘\n’? while scanf(“%c”) does?

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It is consistent behavior, you’re just thinking about it wrong. 😉

scanf("%c", some_char); // reads a character from the key board.
scanf("%d", some_int);  // reads an integer from the key board.

So if I do this:

printf("Insert a character: ");
scanf("%c", &ch);                // if I enter 'f'. Really I entered 'f' + '\n'
                                 // scanf read the first char and left the '\n'
printf("Insert a number: ");
scanf("%d", &actualNum);      // Now scan if is looking for an int, it sees the '\n'
                              // still, but that's not an int so it waits for the 
                              // the next input from stdin

It’s not that it’s consuming the newline on its own in this case. Try this instead:

char ch;
char ch2;
printf("Insert a character: ");
scanf("%c", &ch);
printf("Insert another character: ");
scanf("%c", &ch2);

It will “skip” the second scanf() because it reads in the '\n' at that time. scanf() is consistent and you MUST consume that '\n' if you’re going to use it correctly.

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