datalads-imac:~ yoh$ git annex version
git-annex version: 6.20160221-g3d1895e
...
datalads-imac:~ yoh$ mkdir -p /tmp/123; cd /tmp/123; git init; git annex init;  
Initialized empty Git repository in /private/tmp/123/.git/
init  ok
(recording state in git...)

datalads-imac:123 yoh$  rm -f /tmp/pipe; mkfifo /tmp/pipe; cat /tmp/pipe | git -c receive.autogc=false annex addurl -c annex.largefiles=exclude=*.txt --with-files --json --batch 
{"command":"addurl","file":"1.png","note":"downloading http://www.onerussian.com/tmp/banner.png ..."error: git-annex died of signal 4

# now with --debug
datalads-imac:123 yoh$  rm -f /tmp/pipe; mkfifo /tmp/pipe; cat /tmp/pipe | git -c receive.autogc=false annex addurl -c annex.largefiles=exclude=*.txt --with-files --json --batch --debug
[2016-02-23 08:32:49.160686] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","-c","annex.largefiles=exclude=*.txt","show-ref","git-annex"]
[2016-02-23 08:32:49.167372] process done ExitSuccess
[2016-02-23 08:32:49.167479] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","-c","annex.largefiles=exclude=*.txt","show-ref","--hash","refs/heads/git-annex"]
[2016-02-23 08:32:49.172795] process done ExitSuccess
[2016-02-23 08:32:49.173039] read: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","-c","annex.largefiles=exclude=*.txt","log","refs/heads/git-annex..b2892e67682c5240dadb5d439da810edbdb882df","-n1","--pretty=%H"]
[2016-02-23 08:32:49.178586] process done ExitSuccess
[2016-02-23 08:32:49.179085] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","-c","annex.largefiles=exclude=*.txt","cat-file","--batch"]
[2016-02-23 08:32:49.183985] read: quvi ["--version"]
{"command":"addurl","file":"1.png","note":"downloading http://www.onerussian.com/tmp/banner.png ..."[2016-02-23 08:32:49.255949] call: curl ["-s","-f","-L","-C","-","-#","-o","/private/tmp/123/.git/annex/tmp/URL-s25319--http&c%%www.onerussian.com%tmp%banner.png","http://www.onerussian.com/tmp/banner.png","--user-agent","git-annex/6.20160221-g3d1895e"]
[2016-02-23 08:32:49.302577] process done ExitSuccess
[2016-02-23 08:32:49.303332] chat: git ["--git-dir=.git","--work-tree=.","--literal-pathspecs","-c","annex.largefiles=exclude=*.txt","check-attr","-z","--stdin","annex.backend","annex.numcopies","annex.largefiles","--"]
[2016-02-23 08:32:49.305653] read: git ["--version"]
[2016-02-23 08:32:49.310314] process done ExitSuccess
error: git-annex died of signal 4