From 7effa83470019f75931296c6a5d07a5932c69df8 Mon Sep 17 00:00:00 2001
From: Joey Hess <joey@kitenet.net>
Date: Fri, 1 Aug 2014 17:52:09 -0400
Subject: fix example external remote script to write files atomically

---
 doc/special_remotes/external/example.sh | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

(limited to 'doc/special_remotes/external')

diff --git a/doc/special_remotes/external/example.sh b/doc/special_remotes/external/example.sh
index 5152ccc28..8fed9f4aa 100755
--- a/doc/special_remotes/external/example.sh
+++ b/doc/special_remotes/external/example.sh
@@ -128,14 +128,25 @@ while read line; do
 				STORE)
 					# Store the file to a location
 					# based on the key.
-					# XXX when possible, send PROGRESS
+					# XXX when at all possible, send PROGRESS
 					calclocation "$key"
 					mkdir -p "$(dirname "$LOC")"
-					if runcmd cp "$file" "$LOC"; then
+					# Store in temp file first, so that
+					# CHECKPRESENT does not see it
+					# until it is all stored.
+					mkdir -p "$mydirectory/tmp"
+					tmp="$mydirectory/tmp/$key"
+					if runcmd cp "$file" "$tmp" \
+					   && runcmd mv -f "$tmp" "$LOC"; then
 						echo TRANSFER-SUCCESS STORE "$key"
 					else
 						echo TRANSFER-FAILURE STORE "$key"
 					fi
+
+					mkdir -p "$(dirname "$LOC")"
+					# The file may already exist, so
+					# make sure we can overwrite it.
+					chmod 644 "$LOC" 2>/dev/null || true
 				;;
 				RETRIEVE)
 					# Retrieve from a location based on
-- 
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