[Boost-bugs] [Boost C++ Libraries] #11947: filesystem: getting file_type from a directory_entry without causing a system call on linux

Subject: [Boost-bugs] [Boost C++ Libraries] #11947: filesystem: getting file_type from a directory_entry without causing a system call on linux
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2016-01-29 10:44:32

#11947: filesystem: getting file_type from a directory_entry without causing a
system call on linux
---------------------------------------+--------------------------
 Reporter:  Taru Karttunen <taruti@…>  |      Owner:  bemandawes
     Type:  Patches                    |     Status:  new
Milestone:  To Be Determined           |  Component:  filesystem
  Version:  Boost 1.61.0               |   Severity:  Optimization
 Keywords:                             |
---------------------------------------+--------------------------
 When iterating over a directory with directory_iterator the
 directory_entries are created with the file_type component of the
 m_symlink_status defined if the filesystem supports it on Linux due to
 BOOST_FILESYSTEM_STATUS_CACHE.

 However the directory iteration does not produce the permission component
 of the file status. Thus if using
 `somedirectoryentry.symlink_status().type()` the library performs a
 superfluous lstat system call because status_known does not succeed due to
 permissions_present not succeeding.

 This is possible to fix e.g. by adding a symlink_type method to the
 directory_entry class, a patch implementing it is linked below:

 https://github.com/taruti/filesystem/commit/835bcd3c13697cbd7fc3d8574fd07475eeada398


 ps. Is the documentation manually or automatically created and does it
 need a separate patch?

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/11947>
Boost C++ Libraries <http://www.boost.org/>
Boost provides free peer-reviewed portable C++ source libraries.