Question

I know how scanf could be used for parsing sentences into single words:

while(1){
    scanf("%s", buffer)
    ...
}

However, if I enter a sentence like one two three<return>, how can I find out inside a while-loop if the word I’m getting in the buffer is the one before I pressed <return>?

I guess it is hardly possible with scanf, but maybe there is a similar function?

Answer 1

You should use fgets() to read the whole line, and parse it like so:

char buffer[BUFSIZE] = {};        // BUFSIZE should be large enough for one line
fgets(buffer, BUFSIZE, stdin);    // read from standard input, same as scanf
char *ptr = strtok(buffer, " ");  // second argument is a string of delimiters
                                  // can be " ,." etc.
while (ptr != NULL) {
    printf("Word: '%s'\n", ptr);

    ptr = strtok(NULL, " ");      // note the NULL
}

Checking if the current word is the last word is trivial:

while (ptr != NULL) {
    char word[BUFSIZE] = {};
    strcpy(word, ptr);         // strtok clobbers the string it is parsing
                               // So we copy current string somewhere else.
    ptr = strtok(NULL, " ");

    bool is_last_word = (ptr == NULL);
    // do your thing here with word[]
}