annotate contrib/plan9/README @ 52188:e4b242f9d4d9 stable tip

streamclone: disable the volatile file open handle optimization on Windows

Leaving files open caused new failures like this, since a47f09da8bd1:

    diff --git a/tests/test-persistent-nodemap-stream-clone.t b/tests/test-persistent-nodemap-stream-clone.t
    --- a/tests/test-persistent-nodemap-stream-clone.t
    +++ b/tests/test-persistent-nodemap-stream-clone.t
    @@ -115,7 +115,12 @@ Do a mix of clone and commit at the same
       $ (hg clone -U --stream ssh://user@dummy/test-repo stream-clone-race-1 --debug 2>> clone-output | grep -E '00(changelog|manifest)' >> clone-output; touch $HG_TEST_STREAM_WALKED_FILE_3) &
       $ $RUNTESTDIR/testlib/wait-on-file 10 $HG_TEST_STREAM_WALKED_FILE_1
       $ hg -R test-repo/ commit -m foo
    -  created new head
    +  transaction abort!
    +  failed to recover 00changelog.n ([WinError 32] The process cannot access the file because it is being used by another process: b'$STR_REPR_TESTTMP\\test-repo/.hg/store/00changelog.n' -> b'$STR_REPR_TESTTMP\\test-repo/.hg/store/00changelog.n-f418dcd6')
    +  rollback failed - please run hg recover
    +  (failure reason: [WinError 32] The process cannot access the file because it is being used by another process: b'$STR_REPR_TESTTMP\\test-repo/.hg/store/00changelog.n' -> b'$STR_REPR_TESTTMP\\test-repo/.hg/store/00changelog.n-f418dcd6')
    +  abort: The process cannot access the file because it is being used by another process: '$TESTTMP\test-repo\.hg\store\00changelog.n'
    +  [255]
       $ touch $HG_TEST_STREAM_WALKED_FILE_2
       $ $RUNTESTDIR/testlib/wait-on-file 10 $HG_TEST_STREAM_WALKED_FILE_3
       $ cat clone-output

Since the `VolatileManager` falls back to the old copy method when the open file
threshold is exceeded, this just drops the threshold so that only 1 file is
open.  The actual value used (2) is unexpected, and explained inline.  I'd like
to have a config option for this so that we can test both ways (in theory, it
could resort to copies on non-Windows systems too), but I don't see a `uimod.ui`
handy.

Alternately, I tried replacing the 3 `open()` calls in the `VolatileManager`
with `util.posixfile()`, but that simply hung the test on Windows for some
reason, I think on the same line that's indicated as failing above.  (There was
a `grep` command hanging around, as well as `hg  -R test-repo serve --stdio`.)

Mercurial for Plan 9 from Bell Labs
===================================

This directory contains support for Mercurial on Plan 9 from Bell Labs
platforms. It is assumed that the version of Python running on these
systems supports the ANSI/POSIX Environment (APE). At the time of this
writing, the bichued/python port is the most commonly installed version
of Python on these platforms. If a native port of Python is ever made,
some minor modification will need to be made to support some of the more
esoteric requirements of the platform rather than those currently made
(cf. posix.py).

By default, installations will have the factotum extension enabled; this
extension permits factotum(4) to act as an authentication agent for
HTTP repositories. Additionally, an extdiff command named 9diff is
enabled which generates diff(1) compatible output suitable for use with
the plumber(4).

Commit messages are plumbed using E if no editor is defined; users must
update the plumbed file to continue, otherwise the hg process must be
interrupted.

Some work remains with regard to documentation. Section 5 manual page
references for hgignore and hgrc need to be re-numbered to section 6 (file
formats) and a new man page writer should be written to support the
Plan 9 man macro set. Until these issues can be resolved, manual pages
are elided from the installation.

Basic install:

  % mk install      # do a system-wide install
  % hg debuginstall # sanity-check setup
  % hg              # see help

A proto(2) file is included in this directory as an example of how a
binary distribution could be packaged, ostensibly with contrib(1).

See https://mercurial-scm.org/ for detailed installation
instructions, platform-specific notes, and Mercurial user information.