check defined return value for localized slurp errors

Reading from regular files (even on STDIN) can fail
when dealing with flakey storage.

1 files changed, 1 insertions, 5 deletions

diff --git a/script/public-inbox-init b/script/public-inbox-init
index 6d538e43..7ac77830 100755
--- a/script/public-inbox-init
+++ b/script/public-inbox-init
@@ -100,11 +100,7 @@ if (-e $pi_config) {
         defined $perm or die "(f)stat failed on $pi_config: $!\n";
         chmod($perm & 07777, $fh) or
                 die "(f)chmod failed on future $pi_config: $!\n";
-        my $old;
-        {
-                local $/;
-                $old = <$oh>;
-        }
+        defined(my $old = do { local $/; <$oh> }) or die "read $pi_config: $!\n";
         print $fh $old or die "failed to write: $!\n";
         close $oh or die "failed to close $pi_config: $!\n";