C - minimum singly-linked-list (head/tail - non-circular)

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

enum { MAXLN = 256 };

typedef struct words {
    char *word;
    struct words *next;
} words;

words *add2list (words **list, char *word);
void print_list (words *list);
void free_list (words *list);

int main (int argc, char **argv) {

    words *wordlist = NULL;     /* declare list */
    char line[MAXLN] = {0};     /* line buffer  */
    char delim[] = " \t\n,.;";  /* delimiters   */
    FILE *fp = argc > 1 ? fopen (argv[1], "r") : stdin;

    if (!fp) { /* validate file open */
        fprintf (stderr, "error: file open failed '%s'\n", argv[1]);
        return 1;
    }

    while (fgets (line, MAXLN, fp)) /* read each line in file  */
    {
        char *p = NULL;
        /* tokenize line, add each word in line to linked-list */
        for (p = strtok (line, delim); p; p = strtok (NULL, delim))
            add2list (&wordlist, strdup (p)); /* allocate/copy p  */
    }
    if (fp != stdin) fclose (fp);

    print_list (wordlist);  /* print all nodes in list  */
    free_list  (wordlist);  /* free all nodes in list   */

    return 0;
}

/* add nodes to list */
words *add2list (words **list, char *word)
{
    words *node = calloc (1, sizeof *node); /* create node */
    if (!node) {
        fprintf (stderr, "add2list() error: virtual memory exhausted.\n");
        exit (EXIT_FAILURE);
    }
    node->word = word;  /* assign values */
    node->next = NULL;

    if (!*list) {   /* first node - add as first */
        (*list) = node;
    }
    else {          /* second node - add as next */
        if ((*list)->next == NULL) {
            (*list)->next = node;
        }
        else {      /* remaining nodes - add at end */
            words *iter = *list;
            while (iter->next) iter = iter->next;
            iter->next = node;
        }
    }
    return *list;
}

/* print all nodes in list */
void print_list (words *list)
{
    const words *iter = list;  /* pointer to iterate list  */

    if (iter ==  NULL) {
        fprintf (stderr,"print_list() warning: empty list.\n");
        return;
    }

    for (; iter; iter = (iter->next ? iter->next : NULL))
        printf (" %s\n", iter-> word);
}

/* free all nodes in list */
void free_list (words *list)
{

    words *iter = list;   /* pointer to iterate list  */
    words *victim = list; /* pointer to delete    */

    if (iter ==  NULL) {
        fprintf (stderr,"print_list() warning: empty list.\n");
        return;
    }

    while (iter) {
        victim = iter;
        iter = iter->next;
        free (victim->word);
        free (victim);
    }
}