diff --git a/clite/commands.js b/clite/commands.js
index fe2b0ff..b64f36f 100644
--- a/clite/commands.js
+++ b/clite/commands.js
@@ -50,7 +50,7 @@ Options:
 
 	function writeNodeData(st,fd) {
 		if (long) {
-			if (st.type == 4) {
+			if (st.type == stdio.types.FT_LINK) {
 				var d = stdio.readAll(fd);
 				if (!d)
 					d = '?';
@@ -95,7 +95,7 @@ Options:
 			return;
 		}
 		var st = stdio.fstat(fd);
-		if (!st || st.type != 3) {
+		if (!st || st.type != stdio.types.FT_DIR) {
 			writeNodeData(st,fd);
 			stdio.close(fd);
 			return;
@@ -167,7 +167,7 @@ Options:
 	function fcb(fd) {
 		var st = stdio.fstat(fd);
 		// check if it's a directory or link
-		if (!st || st.type == 3 || st.type == 4) {
+		if (!st || st.type == stdio.types.FT_DIR || st.type == stdio.types.FT_LINK) {
 			if (st) {
 				io.error('not a normal file: '+st.name);
 			}else{
@@ -196,16 +196,16 @@ Options:
 	}
 
 	files.forEach(function(file,index) {
-		var fd = stdio.open(file,fcb);
-		if (!fd) {
-			io.error('cannot open file: '+file);
+		var st = stdio.stat(file);
+		// check if it's a directory or link
+		if (!st || st.type == stdio.types.FT_DIR || st.type == stdio.types.FT_LINK) {
+			io.error('not a normal file: '+file);
 			pending--;
 			return;
 		}
-		var st = stdio.fstat(fd);
-		// check if it's a directory or link
-		if (!st || st.type == 3 || st.type == 4) {
-			io.error('not a normal file: '+file);
+		var fd = stdio.open(file,fcb);
+		if (!fd) {
+			io.error('cannot open file: '+file);
 			pending--;
 			return;
 		}
diff --git a/clite/core.js b/clite/core.js
index 49ed613..f3ed431 100644
--- a/clite/core.js
+++ b/clite/core.js
@@ -714,6 +714,26 @@ clite.io = {
 			return clite.io.fchmod(fd,mode);
 		}
 	},
+	// 0: unknown
+	// 1: text file
+	// 2: executable/binary (function)
+	// 3: directory
+	// 4: link
+	// 5: device
+	// 6: unloaded remote file
+	// 7: shell script
+	// 8: image
+	types:{
+		FT_UNKOWN:0,
+		FT_TEXT:1,
+		FT_BINARY:2,
+		FT_DIR:3,
+		FT_LINK:4,
+		FT_DEV:5,
+		FT_REMOTE:6,
+		FT_SCRIPT:7,
+		FT_IMAGE:8
+	},
 	creat:null,
 	open:null,
 	close:null,
@@ -1633,39 +1653,39 @@ clite.lib = {
 	// 8: image
 		if (fd.node.data.content == null) {
 			if (fd.node.data.remote != null)
-				return 6;
-			return 0;
+				return clite.io.types.FT_REMOTE;
+			return clite.io.types.FT_UNKOWN;
 		}
 		if (fd.node.data.islink)
-			return 4;
+			return clite.io.types.FT_LINK;
 		if (fd.node.data.isdir)
-			return 3;
+			return clite.io.types.FT_DIR;
 		if (fd.node.data.isdev)
-			return 5;
+			return clite.io.types.FT_DEV;
 		const type = typeof fd.node.data.content;
 		switch (type) {
 		case 'string': // text file
 			if (fd.node.data.content.substring(0,2) == '#!')
-				return 7;
-			return 1;
+				return clite.io.types.FT_SCRIPT;
+			return clite.io.types.FT_TEXT;
 			break;
 		case 'function': // executable
-			return 2;
+			return clite.io.types.FT_BINARY;
 			break;
 		case 'object':
 			if (Array.isArray(fd.node.data.content)) // directory
-				return 3;
+				return clite.io.types.FT_DIR;
 			if (fd.node.data.content instanceof HTMLImageElement)
-				return 8;
+				return clite.io.types.FT_IMAGE;
 		case 'symbol':
 		case 'boolean':
 		case 'number':
 		case 'bigint':
 		case 'undefined':
 		default:
-			return 0;
+			return clite.io.types.FT_UNKOWN;
 		}
-		return 0;
+		return clite.io.types.FT_UNKOWN;
 	},
 	getBuffer:function() {
 		return Object.create({