Test fix for MoreShell

MoreShell.c

@@ -25,6 +25,7 @@ main()
 		char buffer[256];
 		readline(0, buffer, 255);
 		buffer[strlen(buffer) - 1] = '\0'; // get rid of cr
+		strcpy(buffer, str_replace(buffer, "~", getenv("HOME")));
 		parse_argv(buffer, argv);
 		if(strcmp("exit", argv[0]) == 0) exit(0);
 		pid_t forkpid;

readline.c

@@ -23,3 +23,47 @@ readline(int fd, char *vptr, size_t maxlen)
 	*ptr = 0;
 	return(n);
 }
+
+char *str_replace(char *orig, char *rep, char *with) {
+    char *result; // the return string
+    char *ins;    // the next insert point
+    char *tmp;    // varies
+    int len_rep;  // length of rep
+    int len_with; // length of with
+    int len_front; // distance between rep and end of last rep
+    int count;    // number of replacements
+
+    if (!orig)
+        return NULL;
+    if (!rep || !(len_rep = strlen(rep)))
+        return NULL;
+    if (!(ins = strstr(orig, rep))) 
+        return NULL;
+    if (!with)
+        with = "";
+    len_with = strlen(with);
+
+    for (count = 0; tmp = strstr(ins, rep); ++count) {
+        ins = tmp + len_rep;
+    }
+
+    // first time through the loop, all the variable are set correctly
+    // from here on,
+    //    tmp points to the end of the result string
+    //    ins points to the next occurrence of rep in orig
+    //    orig points to the remainder of orig after "end of rep"
+    tmp = result = malloc(strlen(orig) + (len_with - len_rep) * count + 1);
+
+    if (!result)
+        return NULL;
+
+    while (count--) {
+        ins = strstr(orig, rep);
+        len_front = ins - orig;
+        tmp = strncpy(tmp, orig, len_front) + len_front;
+        tmp = strcpy(tmp, with) + len_with;
+        orig += len_front + len_rep; // move to next "end of rep"
+    }
+    strcpy(tmp, orig);
+    return result;
+}