support setting No_COW on Perl <5.22

fileno(DIRHANDLE) only works on Perl 5.22+, so we need to use
dirfd(3) ourselves from Inline::C (or rely on chattr(1) being
installed).

While we're at it, rename `set_nodatacow' to `nodatacow_fd'
for consistency with `nodatacow_dir'.

1 files changed, 2 insertions, 2 deletions

diff --git a/lib/PublicInbox/Xapcmd.pm b/lib/PublicInbox/Xapcmd.pm
index 8423194f..714f6859 100644
--- a/lib/PublicInbox/Xapcmd.pm
+++ b/lib/PublicInbox/Xapcmd.pm
@@ -3,9 +3,9 @@
 package PublicInbox::Xapcmd;
 use strict;
 use warnings;
-use PublicInbox::Spawn qw(which popen_rd);
+use PublicInbox::Spawn qw(which popen_rd nodatacow_dir);
 use PublicInbox::Over;
-use PublicInbox::SearchIdx qw(nodatacow_dir);
+use PublicInbox::SearchIdx;
 use File::Temp 0.19 (); # ->newdir
 use File::Path qw(remove_tree);
 use File::Basename qw(dirname);