c - fread() is not returning successfully -

im following tutorial http://c.learncodethehardway.org/book/ex17.html, "learning c hard way", there seems bug function called database_load:

void database_load(struct connection *conn) {     int rc = fread(conn->db, sizeof(struct database), 1, conn->file);     if(rc != 1) die("failed load database."); } 

the function returns "failed load database.".

i tried using debugger, , looked @ fread() docs, i'm unable figure why function returning successfully.

i rewrote function print out tests sanity check:

void database_load(struct connection *conn) {     printf("database_load(struct connection *conn)\n");     if (conn!=0)     {         printf("conn not null\n");         if (conn->file!=0)         {             printf("conn->file not null\n");         }//file not null      }//end conn not null      //actual read filesystem      int rc = fread(conn->db, sizeof(struct database), 1, conn->file);          if (!conn->db!=0)         {             printf("conn->db not null\n");         }//db not null          if(ferror(conn->file))         {       printf("error in reading file\n");         }      if(rc != 1) die("failed load database."); } 

below cmd input:

ps c:\users\xyz\workspace_cpp\the_hard_way\ex17> .\ex_17.exe db.dat s 1 ary ary@yahoo.com 

this program output:

database_load(struct connection *conn)  conn not null  conn->file not null  error: failed load database. 

how can further explore this, might causing issue?

ideas:

1. double-check code opens conn->file. (is open reading, mode "r" or "rb"?)
2. set conn->file null when set database structure; catch case forget open it.
3. temporarily change fread call fread(conn->db, 1, sizeof(struct database), conn->file) , inspect return value; see if it's greater 0 less sizeof(struct database).
4. try calling getc(conn->file) see if eof or character.
5. definitely call perror() or print out strerror(errno) after error.