glacier: Detect when the glacier command in PATH is the wrong one, from boto, rather than from glacier-cli, and refuse to use it, since the boto program fails to fail when passed parameters it does not understand.

doc/bugs/glacier_fails_to_copy.mdwn

@@ -80,3 +80,6 @@ git-annex: copy: 230 failed
 
 # End of transcript or log.
 """]]
+
+> git-annex will now detect this misconfiguration and refuse to use it, so
+> [[done]] --[[Joey]]

doc/bugs/glacier_fails_to_copy/comment_2_b0614f2e7417af733f54c9ff569b11b0._comment

@@ -0,0 +1,33 @@
+[[!comment format=mdwn
+ username="joey"
+ subject="""comment 2"""
+ date="2015-02-06T17:30:50Z"
+ content="""
+Since someone also mentioned this problem on IRC (I don't know if it was
+you), I am wondering if this is an easy mistake to make. I guess so; you
+installed boto from Arch's packages and it included a /usr/bin/glacier..
+Same could happen if using pip to install boto, I think.
+
+I don't want to support multiple different glacier interface programs. The
+eventual plan is to move glacier support into git-annex, using a haskell
+library.
+
+The other concerning thing is that git-annex seems to have reported that
+some of the transfers succeeded. It seems, very unfortunately, that
+the glacier command from boto exits 0 when given unsupported
+parameters. So, git-annex will think a transfer succeeded, at least some of
+the time (sometimes gpg notices that the encrypted output is not all
+consumed).
+
+I think that the best fix will be to make glacier-cli install a
+"glacier-cli" program. Then git-annex can run that instead of "glacier" and
+will be much less likely to run into namespace pollution.
+
+I have filed 2 bug reports:
+
+* [boto's glacier should exit nonzero after displaying usage](https://github.com/boto/boto/issues/2942)
+* [glacier-cli should provide a glacier-cli command](https://github.com/basak/glacier-cli/issues/30)
+
+I have also put a really ugly hack into git-annex to detect when the wrong
+glacier is installed, and refuse to use it.
+"""]]