Index: appfsd.c
==================================================================
--- appfsd.c
+++ appfsd.c
@@ -383,19 +383,19 @@
 	static __thread Tcl_Obj *attr_key_type = NULL, *attr_key_perms = NULL, *attr_key_size = NULL, *attr_key_time = NULL, *attr_key_source = NULL, *attr_key_childcount = NULL;
 	int tcl_ret;
 
 	interp = appfs_TclInterp();
 	if (interp == NULL) {
-		return(1);
+		return(-EIO);
 	}
 
 	tcl_ret = appfs_Tcl_Eval(interp, 2, "::appfs::getattr", path);
 	if (tcl_ret != TCL_OK) {
 		APPFS_DEBUG("::appfs::getattr(%s) failed.", path);
 		APPFS_DEBUG("Tcl Error is: %s", Tcl_GetStringResult(interp));
 
-		return(1);
+		return(-ENOENT);
 	}
 
 	if (attr_key_type == NULL) {
 		attr_key_type       = Tcl_NewStringObj("type", -1);
 		attr_key_perms      = Tcl_NewStringObj("perms", -1);
@@ -409,18 +409,19 @@
 	tcl_ret = Tcl_DictObjGet(interp, attrs_dict, attr_key_type, &attr_value);
 	if (tcl_ret != TCL_OK) {
 		APPFS_DEBUG("[dict get \"type\"] failed");
 		APPFS_DEBUG("Tcl Error is: %s", Tcl_GetStringResult(interp));
 
-		return(1);
+		return(-EIO);
 	}
 
 	if (attr_value == NULL) {
-		return(1);
+		return(-EIO);
 	}
 
 	pathinfo->packaged = 0;
+	pathinfo->inode = appfs_get_path_inode(path);
 
 	attr_value_str = Tcl_GetString(attr_value);
 	switch (attr_value_str[0]) {
 		case 'd': /* directory */
 			pathinfo->type = APPFS_PATHTYPE_DIRECTORY;
@@ -472,11 +473,11 @@
 					memcpy(pathinfo->typeinfo.symlink.source, attr_value_str, attr_value_int);
 				}
 			}
 			break;
 		default:
-			return(1);
+			return(-EIO);
 	}
 
 	Tcl_DictObjGet(interp, attrs_dict, attr_key_time, &attr_value);
 	if (attr_value != NULL) {
 		tcl_ret = Tcl_GetWideIntFromObj(NULL, attr_value, &attr_value_wide);
@@ -577,11 +578,10 @@
 static int appfs_fuse_readdir(const char *path, void *buf, fuse_fill_dir_t filler, off_t offset, struct fuse_file_info *fi) {
 	Tcl_Interp *interp;
 	Tcl_Obj **children;
 	int children_count, idx;
 	int tcl_ret;
-	int retval;
 
 	APPFS_DEBUG("Enter (path = %s, ...)", path);
 
 	interp = appfs_TclInterp();
 	if (interp == NULL) {
@@ -593,19 +593,19 @@
 
 	tcl_ret = appfs_Tcl_Eval(interp, 2, "::appfs::getchildren", path);
 	if (tcl_ret != TCL_OK) {
 		APPFS_DEBUG("::appfs::getchildren(%s) failed.", path);
 		APPFS_DEBUG("Tcl Error is: %s", Tcl_GetStringResult(interp));
-		
+
 		return(0);
 	}
 
 	tcl_ret = Tcl_ListObjGetElements(interp, Tcl_GetObjResult(interp), &children_count, &children);
 	if (tcl_ret != TCL_OK) {
 		APPFS_DEBUG("Parsing list of children on path %s failed.", path);
 		APPFS_DEBUG("Tcl Error is: %s", Tcl_GetStringResult(interp));
-		
+
 		return(0);
 	}
 
 	for (idx = 0; idx < children_count; idx++) {
 		filler(buf, Tcl_GetString(children[idx]), NULL, 0);
@@ -613,45 +613,66 @@
 
 	return(0);
 }
 
 static int appfs_fuse_open(const char *path, struct fuse_file_info *fi) {
+	Tcl_Interp *interp;
 	struct appfs_pathinfo pathinfo;
-	const char *real_path;
+	const char *real_path, *mode;
+	int gpi_ret, tcl_ret;
 	int fh;
-	int gpi_ret;
 
 	APPFS_DEBUG("Enter (path = %s, ...)", path);
 
-#if 0
-
-	if ((fi->flags & 3) != O_RDONLY) {
-                return(-EACCES);
-	}
-
-	gpi_ret = appfs_get_path_info(path, &pathinfo, NULL);
-	if (gpi_ret != 0) {
-		return(gpi_ret);
+	gpi_ret = appfs_get_path_info(path, &pathinfo);
+
+	if ((fi->flags & (O_WRONLY|O_CREAT)) == (O_CREAT|O_WRONLY)) {
+		/* The file will be created if it does not exist */
+		if (gpi_ret != 0 && gpi_ret != -ENOENT) {
+			return(gpi_ret);
+		}
+
+		mode = "create";
+	} else {
+		/* The file must already exist */
+		if (gpi_ret != 0) {
+			return(gpi_ret);
+		}
+
+		mode = "";
 	}
 
 	if (pathinfo.type == APPFS_PATHTYPE_DIRECTORY) {
 		return(-EISDIR);
 	}
 
-	real_path = appfs_getfile(pathinfo.hostname, pathinfo.typeinfo.file.sha1);
+	interp = appfs_TclInterp();
+	if (interp == NULL) {
+		return(-EIO);
+	}
+
+	tcl_ret = appfs_Tcl_Eval(interp, 3, "::appfs::openpath", path, mode);
+	if (tcl_ret != TCL_OK) {
+		APPFS_DEBUG("::appfs::openpath(%s, %s) failed.", path, mode);
+		APPFS_DEBUG("Tcl Error is: %s", Tcl_GetStringResult(interp));
+
+		return(-EIO);
+	}
+
+	real_path = Tcl_GetStringResult(interp);
 	if (real_path == NULL) {
 		return(-EIO);
 	}
 
-	fh = open(real_path, O_RDONLY);
-	free((void *) real_path);
+	APPFS_DEBUG("Translated request to open %s to opening %s (mode = \"%s\")", path, real_path, mode);
+
+	fh = open(real_path, fi->flags, 0600);
 	if (fh < 0) {
 		return(-EIO);
 	}
 
 	fi->fh = fh;
-#endif
 
 	return(0);
 }
 
 static int appfs_fuse_close(const char *path, struct fuse_file_info *fi) {
@@ -776,11 +797,11 @@
 
 /*
  * FUSE option parsing callback
  */
 static int appfs_fuse_opt_cb(void *data, const char *arg, int key, struct fuse_args *outargs) {
-	static seen_cachedir = 0;
+	static int seen_cachedir = 0;
 
 	if (key == FUSE_OPT_KEY_NONOPT && seen_cachedir == 0) {
 		seen_cachedir = 1;
 
 		appfs_cachedir = strdup(arg);

Index: appfsd.tcl
==================================================================
--- appfsd.tcl
+++ appfsd.tcl
@@ -36,11 +36,11 @@
 
 		if {[file exists $file]} {
 			return $file
 		}
 
-		set tmpfile "${file}.[expr {rand()}]"
+		set tmpfile "${file}.[expr {rand()}][clock clicks]"
 
 		set fd [open $tmpfile "w"]
 		fconfigure $fd -translation binary
 
 		catch {
@@ -342,10 +342,11 @@
 	}
 
 	proc _localpath {package hostname file} {
 		set homedir [::appfsd::get_homedir]
 		set dir [file join $homedir .appfs "./${package}@${hostname}" "./${file}"]
+		return $dir
 	}
 
 	proc _parsepath {path} {
 		set path [string trim $path "/"]
 		set path [split $path "/"]
@@ -527,7 +528,39 @@
 
 		return [array get retval]
 	}
 
 	proc openpath {path mode} {
+		array set pathinfo [_parsepath $path]
+
+		if {$pathinfo(_type) != "files"} {
+			return -code error "invalid type"
+		}
+
+		set localpath [_localpath $pathinfo(package) $pathinfo(hostname) $pathinfo(file)]
+
+		if {[file exists $localpath]} {
+			return $localpath
+		}
+
+		set work [split $pathinfo(file) "/"]
+		set directory [join [lrange $work 0 end-1] "/"]
+		set file [lindex $work end]
+		set file_sha1 [::appfs::db onecolumn {SELECT file_sha1 FROM files WHERE package_sha1 = $pathinfo(package_sha1) AND file_name = $file AND file_directory = $directory;}]
+
+		if {$file_sha1 == ""} {
+			return -code error "No such file or directory"
+		}
+
+		set localcachefile [download $pathinfo(hostname) $file_sha1]
+
+		if {$mode == "create"} {
+			set tmplocalpath "${localpath}.[expr rand()][clock clicks]"
+			file copy -force -- $localcachefile $tmplocalpath
+			file rename -force -- $tmplocalpath $localpath
+
+			return $localpath
+		}
+
+		return $localcachefile
 	}
 }