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Doug Cutting commented on HADOOP-4108: -------------------------------------- > public FsAction access(Path p) throws IOException { ... } This requires an RPC per file when processing directories. I think it's better to hang this method off of FileStatus, so that requests to the remote FileSystem can be batched for directories. > FileSystem support for POSIX access method > ------------------------------------------ > > Key: HADOOP-4108 > URL: https://issues.apache.org/jira/browse/HADOOP-4108 > Project: Hadoop Core > Issue Type: New Feature > Components: fs > Reporter: Pete Wyckoff > Assignee: Pete Wyckoff > > From man access: > {code} > int access(const char *pathname, int mode); > {code} > DESCRIPTION > access checks whether the process would be allowed to read, write > or test for existence of the file (or other file system object) whose name is > pathname. If pathname is a symbolic link permissions of the file referred to > by this symbolic link are tested. > mode is a mask consisting of one or more of R_OK, W_OK, X_OK and F_OK. > R_OK, W_OK and X_OK request checking whether the file exists and has > read, write and execute permissions, respectively. F_OK just requests > checking for the existence of the file. > The tests depend on the permissions of the directories occurring in > the path to the file, as given in pathname, and on the permissions of > directories and files referred to by symbolic links encountered on the way. > The check is done with the processâs real uid and gid, rather than > with the effective ids as is done when actually attempting an operation. > This is to allow set-UID programs to > easily determine the invoking userâs authority. > Only access bits are checked, not the file type or contents. > Therefore, if a directory is found to be "writable," it probably means that > files can be created in the directory, > and not that the directory can be written as a file. Similarly, a DOS > file may be found to be "executable," but the execve(2) call will still fail. > If the process has appropriate privileges, an implementation may > indicate success for X_OK even if none of the execute file permission bits > are set. > RETURN VALUE > On success (all requested permissions granted), zero is returned. On > error (at least one bit in mode asked for a permission that is denied, or > some other error occurred), -1 is > returned, and errno is set appropriately. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.