[PATCH v2 0/6] Implement clearenv

[Ken Brown]

This is a followup to https://cygwin.com/ml/cygwin/2018-05/msg00334.html.

In this patch series I attempt to implement the glibc extension
clearenv(). I also implement glibc's notion of environ==NULL being
shorthand for an empty environment.

v2: In patch 2 I've tried harder to fix all the cases in which
environ==NULL could be a problem.  I did this by grepping the sources
for 'cur_environ' and '__cygwin_environ', but it's still possible that
I missed something.

I've also incorporated the changes suggested by Corinna and Yaakov.

Ken Brown (6):
  Cygwin: Clarify some code in environ.cc
  Cygwin: Allow the environment pointer to be NULL
  Cygwin: Implement the GNU extension clearenv
  Cygwin: Remove workaround in environ.cc
  Cygwin: Document clearenv and bump API minor
  Bump Cygwin DLL version to 2.11.0

 winsup/cygwin/common.din                 |  1 +
 winsup/cygwin/environ.cc                 | 56 +++++++++++++++++++-----
 winsup/cygwin/include/cygwin/stdlib.h    |  3 ++
 winsup/cygwin/include/cygwin/version.h   |  7 +--
 winsup/cygwin/pinfo.cc                   |  7 +--
 winsup/cygwin/release/{2.10.1 => 2.11.0} |  1 +
 winsup/doc/new-features.xml              | 20 +++++++++
 winsup/doc/posix.xml                     |  1 +
 8 files changed, 80 insertions(+), 16 deletions(-)
 rename winsup/cygwin/release/{2.10.1 => 2.11.0} (97%)

-- 
2.17.0