os: Readdir fails, if one of the files cannot be accessed

[bancek]

If directory contains file that cannot be accessed (if lstat fails), f.Readdir fails with an error.

Error can be reproduced using custom FUSE driver.

https://gist.github.com/bancek/4adadd65597a2da44a49

Bash fails to show info for that dir but still lists other files.

$ mkdir foo bar
$ ./deny foo
$ ls -al
ls: cannot access foo: Permission denied
total 20
drwxrwxr-x   4 luka luka  4096 Jun 16 17:28 .
drwxrwxr-x 233 luka luka 12288 Jun 16 16:26 ..
drwxrwxr-x   2 luka luka  4096 Jun 16 17:28 bar
d?????????   ? ?    ?        ?            ? foo

Readdir fails with lstat permission denied (http://play.golang.org/p/G_yZ94rkRs).

$ go run ../readdirtest.go 
panic: lstat ./foo: permission denied

Readdirnames works fine (http://play.golang.org/p/WY-uBxCjpd).

$ go run ../readdirnamestest.go 
[foo bar]

[bradfitz]

This is working as designed and documented: "In this case, if Readdir succeeds (reads all the way to the end of the directory), it returns the slice and a nil error. If it encounters an error before the end of the directory, Readdir returns the FileInfo read until that point and a non-nil error."

I think you already found the answer: use Readdirnames.