dictionary file location

Makefile

@@ -8,6 +8,7 @@ debug: main.c
 
 install: default
 	cp banagram /usr/bin/banagram
+	cp -n words /usr/share/dict/banawords
 
 uninstall:
 	rm /usr/bin/banagram

main.c

@@ -4,6 +4,8 @@
 #include <ctype.h>
 #include <stdbool.h>
 
+#define DICTFILE "/usr/share/dict/banawords"
+
 /*
  * Copyright 2020 Alistair Michael
  * 
@@ -60,10 +62,23 @@ int *count_char(char *word) {
     }
     return counts;
 }
+
+FILE *open_dict_file(char *filename) {
+    FILE *wfile = fopen(filename, "r");
+
+    if (!wfile) {
+        fprintf(stderr, "Unable to open dict\n");
+        exit(1);
+    }
+
+    return wfile;
+}
+
 // @param allowed: additional characters allowed in anagram match, 
 // set to NULL to allow matching any set of characters.
 int get_minimum_match(char *word, int added, char *allowed) {
-    FILE *wfile = fopen("words", "r");
+    FILE* wfile = open_dict_file(DICTFILE);
+
     char line[LINELENGTH];
     int err;
     int len = strlen(word);
@@ -97,6 +112,10 @@ int get_minimum_match(char *word, int added, char *allowed) {
 
         if (allowed) {
             max_letter_counts = count_char(allowed);
+            if (!max_letter_counts) {
+                return 1;
+            }
+
             for (int i = 0; i < 26; i++) {
                 max_letter_counts[i] += orig_word_letter_counts[i];
             }
@@ -150,9 +169,11 @@ int get_minimum_match(char *word, int added, char *allowed) {
     return 0;
 }
 
+
 int get_exact_anag(char *word) {
-    FILE *wfile = fopen("words", "r");
+
     make_lowercase(word);
+    FILE* wfile = open_dict_file(DICTFILE);
 
     char line[LINELENGTH];
     int err;