Alex Clemmer created MESOS-5880:
-----------------------------------
Summary: Make `environment` semantics uniform across Windows and
POSIX
Key: MESOS-5880
URL: https://issues.apache.org/jira/browse/MESOS-5880
Project: Mesos
Issue Type: Bug
Components: stout
Reporter: Alex Clemmer
Assignee: Alex Clemmer
Preliminary investigation shows that our current Windows implementations of
`os::environment`, `os::setenv`, and `os::getenv` fail to set flags in some
cases. This leads to test failures on Windows in:
* `flags_tests.cpp` (MESOS-3437), namely `LoadFromEnvironment`
* `os_tests.cpp` (MESOS-3441), namely `Environment`
A preliminary investigation shows:
* These failures occur because the C standard API for environment variables are
incompatible. That is, `os::environment` uses the C standard implementation of
the `environ` macro, while `os::setenv` and `os::putenv` use the Win32 APIs for
environment variables, like `GetEnvironmentVariable` and
`SetEnvironmentVariable`. But, `SetEnvironmentVariable` does not affect the
environment reported by `environ`, so updates are not reflected when we call
`os::environ`.
* It is unlikely we will want to use the C equivalents of the
`Get/SetEnvironmentVariable`, (that is, `setenv_s` and friends), because they
have different behavior on Windows than on other libc implementations.
Specifically, on Windows `setenv_s("yourvar", "")` unsets the variable
`yourvar`, while on other implementations, it sets the value of `yourvar` to be
the empty string.
* But, transitioning to a pure Win32 implementation (i.e., one using
`Set/GetEnvironmentVariable`, `GetEnvironmentStrings`, etc.), probably requires
changing or getting rid of `os::environment*` APIs. Specifically,
`os::raw::environment` and `os::environmentp` will probably be eliminated.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
