Using strings from a text file is working different than using literal strings?

Question

I have a C program that is reading strings from a text file and using these to create structs which are being placed in a hash table (d_table). It reads from a file line by line in a loop. The runtime problem I get is that every entry added using strings taken from a file all seem to still be pointing to whatever was most recently read (so char word[] would just be "."), BUT if it was to hard code in some entries (like the second ht_insert) then it works fully as expected. This makes me think that I am missing something obvious in how C handles strings...

A line of the text file looks like: "Test This is a test line", with the last line being a "."

entry struct:

struct d_entry {
  char *word;
  char *desc;
};

I don't think the problem is caused at create_entry or beyond in the program, otherwise why would hard coded entries work perfectly fine? As far as I know, beyond this point entries should be indistinguishable whether the strings were hard coded or taken from a file:

struct d_entry * create_entry(char *word, char*desc) {
  struct d_entry * e;
  e = (struct d_entry *) malloc(sizeof(struct d_entry));
  e->word = word;
  e->desc = desc;
  return e;
}

This is the necessary code taken from the function reading from file. I have tested plenty and the file handling and the extracting of strings from files seems to be working correctly: The first ht_insert call causes the runtime problem, the second call is an example of hard coding an entry which works perfectly correctly:

int read_from_file(const char * filename) {

  char word[40];
  char desc[200];

  FILE * fp;
  fp = fopen(filename, "r");

  fscanf(fp, "%s %[^\n]]", word, desc);

  while (word[0] != '.') {
    ht_insert (d_table, create_entry(word, desc)):
    ht_insert (d_table, create_entry("test", "test desc"));
    fscanf(fp, "%s %[^\n]", word, desc);
  }

fclose(fp);
return 1;
}

Any help would be greatly appreciated, thanks.

Answer 1

create_entry(strdup(word), strdup(desc))

Answer 2

Use strdup to make a heap copy of each string you store in your data structure.

Do that for both strings read from file (into temp buffer) and static strings.