> On June 21, 2016, 5:33 p.m., Jiang Yan Xu wrote: > > 3rdparty/stout/include/stout/os/empty.hpp, line 37 > > <https://reviews.apache.org/r/48314/diff/5/?file=1425826#file1425826line37> > > > > Looks like the Windows version of `readdir` and its internal calls do > > set errno > > ([exmaple](https://github.com/apache/mesos/blob/56503ea6547c65de7e3e7b294419400894d54003/3rdparty/stout/include/stout/internal/windows/dirent.hpp#L133)) > > so we don't have to explicitly set things here. > > Jiang Yan Xu wrote: > I see. You are right. If there's no error, errno is not guaranteed to be > zero unless we set it here.
As discussed with Yan: As a general pattern, `errno` is set to the actual error within the context of system calls when the system call returns failure. However, the system call as a rule is not required to set it to 0 on success. Therefore, the pattern is to initialize `errno` to 0, and depend on `errno` for the actual error if the system call fails. Hence, I think we should keep it as is. > On June 21, 2016, 5:33 p.m., Jiang Yan Xu wrote: > > 3rdparty/stout/include/stout/os/empty.hpp, line 42 > > <https://reviews.apache.org/r/48314/diff/5/?file=1425826#file1425826line42> > > > > No need for this. > > Jiang Yan Xu wrote: > If the set `errno = 0`, do we still need it here? Same as previous comment (https://reviews.apache.org/r/48314/#comment204090). - Anindya ----------------------------------------------------------- This is an automatically generated e-mail. To reply, visit: https://reviews.apache.org/r/48314/#review138888 ----------------------------------------------------------- On June 21, 2016, 6:40 p.m., Anindya Sinha wrote: > > ----------------------------------------------------------- > This is an automatically generated e-mail. To reply, visit: > https://reviews.apache.org/r/48314/ > ----------------------------------------------------------- > > (Updated June 21, 2016, 6:40 p.m.) > > > Review request for mesos, Neil Conway and Jiang Yan Xu. > > > Bugs: MESOS-5448 > https://issues.apache.org/jira/browse/MESOS-5448 > > > Repository: mesos > > > Description > ------- > > Added os::empty(path) to check if contents in a directory is empty. > > > Diffs > ----- > > 3rdparty/stout/include/Makefile.am f10c836c1ac008cc4055741648b5e7dd697e4c1e > 3rdparty/stout/include/stout/os.hpp > 53b00932693fba7cf6514da6a519269a904de345 > 3rdparty/stout/include/stout/os/empty.hpp PRE-CREATION > 3rdparty/stout/tests/os/rmdir_tests.cpp > a11bfc9f9e6cbb05f3e9ce0ea48297b8f88fe53f > > Diff: https://reviews.apache.org/r/48314/diff/ > > > Testing > ------- > > All tests passed. > > > Thanks, > > Anindya Sinha > >
