From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeff King <peff@peff.net>
Subject: Re: [PATCH 5/9] add test for streaming corrupt blobs
Date: Wed, 27 Mar 2013 16:27:05 -0400
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 <20130325202134.GE16019@sigill.intra.peff.net>
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On Mon, Mar 25, 2013 at 04:21:34PM -0400, Jeff King wrote:

> +# Convert byte at offset "$2" of object "$1" into '\0'
> +corrupt_byte() {
> +	obj_file=$(obj_to_file "$1") &&
> +	chmod +w "$obj_file" &&
> +	printf '\0' | dd of="$obj_file" bs=1 seek="$2"
> +}

Hmm, this last line should probably be:

diff --git a/t/t1060-object-corruption.sh b/t/t1060-object-corruption.sh
index a84deb1..3f87051 100755
--- a/t/t1060-object-corruption.sh
+++ b/t/t1060-object-corruption.sh
@@ -12,7 +12,7 @@ corrupt_byte() {
 corrupt_byte() {
 	obj_file=$(obj_to_file "$1") &&
 	chmod +w "$obj_file" &&
-	printf '\0' | dd of="$obj_file" bs=1 seek="$2"
+	printf '\0' | dd of="$obj_file" bs=1 seek="$2" conv=notrunc
 }
 
 test_expect_success 'setup corrupt repo' '

The intent was to change a single byte, not truncate the file (though on
the plus side, that truncation is what found the other bugs).

-Peff