commit - 5f1e81058a16f2139f47022131a02ea597e003cc
commit + c979b5e1f8a799f06a75c3affd19126f5d57d020
blob - 22235424d65bc142f1cb44c60aa1ccf7012ed76b
blob + 6a21069e2335562348947f852752d1a70734bc25
--- errors.go
+++ errors.go
@@ -5,16 +5,45 @@ import (
 	"fmt"
 )
 
-type Error struct {
+// common errors returned by Session interface methods
+var (
+	ErrClosed = errors.New("closed")
+)
+
+// 9p wire errors returned by Session interface methods
+var (
+	ErrBadattach    = new9pError("unknown specifier in attach")
+	ErrBadoffset    = new9pError("bad offset")
+	ErrBadcount     = new9pError("bad count")
+	ErrBotch        = new9pError("9P protocol botch")
+	ErrCreatenondir = new9pError("create in non-directory")
+	ErrDupfid       = new9pError("duplicate fid")
+	ErrDuptag       = new9pError("duplicate tag")
+	ErrIsdir        = new9pError("is a directory")
+	ErrNocreate     = new9pError("create prohibited")
+	ErrNomem        = new9pError("out of memory")
+	ErrNoremove     = new9pError("remove prohibited")
+	ErrNostat       = new9pError("stat prohibited")
+	ErrNotfound     = new9pError("file not found")
+	ErrNowrite      = new9pError("write prohibited")
+	ErrNowstat      = new9pError("wstat prohibited")
+	ErrPerm         = new9pError("permission denied")
+	ErrUnknownfid   = new9pError("unknown fid")
+	ErrBaddir       = new9pError("bad directory in wstat")
+	ErrWalknodir    = new9pError("walk in non-directory")
+
+	// extra errors not part of the normal protocol
+	ErrTimeout = new9pError("fcall timeout") // returned when timing out on the fcall
+)
+
+type error9p struct {
 	Name string
 }
 
-func (e Error) Error() string {
-	return fmt.Sprintf("9p: %v", e.Name)
+func new9pError(s string) error {
+	return &error9p{Name: s}
 }
 
-var (
-	ErrClosed = errors.New("closed")
-
-	ErrUnknownfid = Error{Name: "unknown fid"}
-)
+func (e error9p) Error() string {
+	return fmt.Sprintf("9p: %v", e.Name)
+}