io.c: fix IO.copy_stream on O_APPEND destination on Linux
Linux copy_file_range(2) fails with EBADF if the destination FD
has O_APPEND set. Preserve existing (Ruby <= 2.4) behavior by
falling back to alternative copy mechanisms if this is the case
(instead of raising Errno::EBADF).
io.c (nogvl_copy_file_range): do not raise on O_APPEND dst
test/ruby/test_io.rb (test_copy_stream_append): new test
[Feature #13867]
io.c: fix IO.copy_stream on O_APPEND destination on Linux
Linux copy_file_range(2) fails with EBADF if the destination FD
has O_APPEND set. Preserve existing (Ruby <= 2.4) behavior by
falling back to alternative copy mechanisms if this is the case
(instead of raising Errno::EBADF).
[Feature #13867]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@60490 b2dd03c8-39d4-4d8f-98ff-823fe69b080e