如何调用使用结构指针函数填充的结构的成员

Question

I would like to know how to print the value of char* word from this structure.

  struct word_count_struct {
  char *word;
  int   count;
};

This structure has been given a value thought the function

struct word_count_struct *new_word_count( char *word )
{
    struct word_count_struct *new_word_count = (struct word_count_struct *)malloc(sizeof(struct word_count_struct));

    new_word_count->word = "Hello";
    new_word_count->count = 1; 

    return new_word_count;    
}

When I use word_count_struct new_word_count( &word ); or new_word_count( &word ); to call the function and puts(new_word_count->word); to print the member from main.c,

I get the error message

error: called object ‘new_word_count’ is not a function or function pointer

and

note: declared here
     struct word_count_struct *new_word_count;

What I am specifically not sure about is the function call, I know with any other function i would generally use the code function_name(passing arguments); but this function returns a struct pointer and there seems to be two names within the function signature.

If I do not use a function to assign value to the struct members, I am able to print out the value of new_word_count->word within main.c no problem, so I believe my issues must come from the function call. Thank you in advance.

Minimal, Complete and verifiable example:

#include <stdio.h>
#include <stdlib.h>

struct word_count_struct {
  char *word;
  int count;
};

struct word_count_struct *new_word_count( char *word );

int main()
{
    struct word_count_struct *wordcountptr;
    char *word = "Hello";

    wordcountptr = new_word_count(word);
    puts(wordcountptr->word); /* print out the string "Hello" which was assigned to this struct member though the word_count_struct function */
    free(wordcountptr);
    return 0;
}

/* this function should take the value of the passing argument and assign it to the word member of struct word_count_struct and then return a pointer to that struct */
struct word_count_struct *new_word_count( char *word )
{
    struct word_count_struct *new_word_count;
    new_word_count = (struct word_count_struct *)malloc(sizeof(struct word_count_struct)); /* allocate memory for struct */

    new_word_count->word = &word; /* assign the memory address of passing argument to this member */
    new_word_count->count = 1;

    return new_word_count;

}

Answer 1

You probably want this:

struct word_count_struct *wordcountptr;
char *word;
wordcountptr = new_word_count(word);
puts(wordcountptr->word);

this code compiles and runs but it is more or less useless because the new_word_count function is not finished.

Question has changed...

The problem is now here:

You need this:

new_word_count->word = word;

instead of

new_word_count->word = &word;

BTW your compiler should have warned you.

Complete function:

struct word_count_struct *new_word_count(char *word)
{
  struct word_count_struct *new_word_count;
  new_word_count = (struct word_count_struct *)malloc(sizeof(struct word_count_struct));

  new_word_count->word = word;
  new_word_count->count = 1;

  return new_word_count;
}

But with this approach you will most likely run into other problems because you only store the address of the word to be counted, but you probably rather want to store the word itself. Instead of:

new_word_count->word = word;

you probably need:

new_word_count->word = malloc(strlen(word) + 1);  // allocate memory for word
strcpy(new_word_count->word, word);               // copy the word