chgserver: remove Python 2 file descriptor logic
Follows up 0bb28b7736bc "chgserver: remove Python 2 support code."
On Python 2, we had to close newfp prior to restoring the original file
description since "delete newfp" would otherwise close the file descriptor
shared with the long-lived fp:
in attachio():
newfp = os.fdopen(fp.fileno(), mode, bufsize)
in _restoreio():
newfp.close() # temporarily close newfp.fileno() (= fp.fileno())
os.dup2(fd, fp.fileno()) # reopen fp.fileno() with original fd
On the other hand, we shouldn't call newfp.close() on Python 3 since
any function calls are proxied to the underlying file object by
procutil.LineBufferedWrapper.
syntax: glob
*.elc
*.tmp
*.orig
*.rej
*~
*.mergebackup
*.o
*.so
*.dll
*.exe
*.pyd
*.pyc
*.pyo
*$py.class
*.swp
*.prof
*.zip
\#*\#
.\#*
tests/artifacts/cache/big-file-churn.hg
tests/.coverage*
tests/.testtimes*
tests/.hypothesis
tests/hypothesis-generated
tests/annotated
tests/exceptions
tests/python3
tests/*.err
tests/htmlcov
build
contrib/chg/chg
contrib/hgsh/hgsh
contrib/vagrant/.vagrant
dist
packages
doc/common.txt
doc/*.[0-9]
doc/*.[0-9].txt
doc/*.[0-9].gendoc.txt
doc/*.[0-9].{x,ht}ml
MANIFEST
MANIFEST.in
patches
mercurial/__modulepolicy__.py
mercurial/__version__.py
mercurial/hgpythonlib.h
mercurial.egg-info
.DS_Store
tags
cscope.*
.vscode/*
.idea/*
.asv/*
.pytype/*
.mypy_cache
i18n/hg.pot
locale/*/LC_MESSAGES/hg.mo
hgext/__index__.py
rust/target/
rust/*/target/
# Generated wheels
wheelhouse/
syntax: rootglob
# See Profiling in rust/README.rst
.cargo/config
syntax: regexp
^\.pc/
^\.(pydev)?project
# hackable windows distribution additions
^hg-python
^hg.py$