diff --git a/sync.c b/sync.c
index fbe95f9..6aee9ae 100644
--- a/sync.c
+++ b/sync.c
@@ -16,32 +16,114 @@ static int c2pstr(Str255 ostr, const char *istr) {
 	return 0;
 }
 
-static int list_dir(const char *dirpath) {
+struct file_meta {
+	Boolean exists;
+	long modTime;
+};
+
+enum {
+	kSrcDir,
+	kDestDir,
+};
+
+struct file_info {
+	Str31 name;
+	struct file_meta meta[2];
+};
+
+static Handle gFiles;
+static unsigned gFileCount;
+static unsigned gFileAlloc;
+
+static struct file_info *get_file(const unsigned char *name) {
+	unsigned i, n = gFileCount, len, newAlloc;
+	struct file_info *file, *array;
+	Handle newFiles;
+	OSErr err;
+
+	len = name[0];
+	if (len > 31) {
+		fputs("## Error: name too long\n", stderr);
+		return NULL;
+	}
+	if (gFiles == NULL) {
+		newAlloc = 8;
+		newFiles = NewHandle(newAlloc * sizeof(struct file_info));
+		err = MemError();
+		if (err != noErr) {
+			fputs("## Error: out of memory\n", stderr);
+			return NULL;
+		}
+		gFiles = newFiles;
+		gFileAlloc = newAlloc;
+	} else {
+		array = (struct file_info *)*gFiles;
+		for (i = 0; i < n; i++) {
+			file = &array[i];
+			if (memcmp(file->name, name, len + 1) == 0) {
+				return file;
+			}
+		}
+		if (n >= gFileAlloc) {
+			newAlloc = n * 2;
+			SetHandleSize(gFiles, newAlloc * sizeof(struct file_info));
+			err = MemError();
+			if (err != noErr) {
+				fputs("## Error: out of memory\n", stderr);
+				return NULL;
+			}
+			gFileAlloc = newAlloc;
+		}
+	}
+	array = (struct file_info *)*gFiles;
+	file = &array[n];
+	gFileCount = n + 1;
+	memset(file, 0, sizeof(*file));
+	memcpy(file->name, name, len + 1);
+	return file;
+}
+
+static int dir_from_path(short *vRefNum, long *dirID, const char *dirpath) {
 	Str255 ppath;
+	FSSpec spec;
 	CInfoPBRec ci;
 	OSErr err;
-	short vRefNum;
-	long dirID;
-	int i;
 
 	if (c2pstr(ppath, dirpath)) {
 		return 1;
 	}
+	err = FSMakeFSSpec(0, 0, ppath, &spec);
+	if (err != 0) {
+		fprintf(stderr, "## Error: FSMakeFSSpec: %d\n", err);
+		return 1;
+	}
+	printf("vol = %d, dir = %ld\n", spec.vRefNum, spec.parID);
 	memset(&ci, 0, sizeof(ci));
-	ci.dirInfo.ioNamePtr = ppath;
+	ci.dirInfo.ioNamePtr = spec.name;
+	ci.dirInfo.ioVRefNum = spec.vRefNum;
+	ci.dirInfo.ioDrDirID = spec.parID;
 	err = PBGetCatInfoSync(&ci);
 	if (err != 0) {
 		fprintf(stderr, "## Error: PBGetCatInfoSync: %d\n", err);
 		return 1;
 	}
-	vRefNum = ci.dirInfo.ioVRefNum;
-	dirID = ci.dirInfo.ioDrDirID;
-	printf("vRefNum: %d; dirID: %d\n", vRefNum, dirID);
 	if ((ci.dirInfo.ioFlAttrib & kioFlAttribDirMask) == 0) {
 		fprintf(stderr, "## Error: not a directory: %s\n", dirpath);
 		return 1;
 	}
+	*vRefNum = ci.dirInfo.ioVRefNum;
+	*dirID = ci.dirInfo.ioDrDirID;
+	return 0;
+}
 
+static int list_dir(short vRefNum, long dirID, int which) {
+	Str255 ppath;
+	CInfoPBRec ci;
+	OSErr err;
+	int i;
+
+	printf("FILES\n");
+	(void)which;
 	for (i = 1; i < 100; i++) {
 		memset(&ci, 0, sizeof(ci));
 		ci.dirInfo.ioNamePtr = ppath;
@@ -53,9 +135,8 @@ static int list_dir(const char *dirpath) {
 			if (err == fnfErr) {
 				break;
 			}
-			fprintf(stderr,
-			        "## Error: could not list directory '%s' (err = %d)\n",
-			        dirpath, err);
+			fprintf(stderr, "## Error: could not list directory (err = %d)\n",
+			        err);
 			continue;
 		}
 		ppath[ppath[0] + 1] = '\0';
@@ -65,13 +146,43 @@ static int list_dir(const char *dirpath) {
 	return 0;
 }
 
-int main(int argc, char **argv, char **envp) {
-	int i;
-	(void)envp;
-	for (i = 1; i < argc; i++) {
-		if (list_dir(argv[i])) {
-			return 1;
-		}
+static int command_main(char *destpath) {
+	short srcVol, destVol;
+	long srcDir, destDir;
+	OSErr err;
+	int r;
+
+	err = HGetVol(NULL, &srcVol, &srcDir);
+	if (err != 0) {
+		fprintf(stderr, "## Error: HGetVol: %d\n", err);
+		return 1;
 	}
+	r = dir_from_path(&destVol, &destDir, destpath);
+	if (r != 0) {
+		return 1;
+	}
+	r = list_dir(srcVol, srcDir, kSrcDir);
+	if (r != 0) {
+		return 1;
+	}
+	r = list_dir(destVol, destDir, kDestDir);
+	if (r != 0) {
+		return 1;
+	}
+
 	return 0;
 }
+
+int main(int argc, char **argv) {
+	int r;
+
+	if (argc != 2) {
+		fputs("## Usage: SyncFiles <directory>\n", stderr);
+		return 1;
+	}
+	r = command_main(argv[1]);
+	if (gFiles != NULL) {
+		DisposeHandle(gFiles);
+	}
+	return r;
+}