avoid uname -o on !linux and catch any exception from it

Fix bug in last release that prevented the webapp opening on non-Linux systems.

This commit was sponsored by Jake Vosloo on Patreon.

CHANGELOG

@@ -1,12 +1,14 @@
 git-annex (6.20180428) UNRELEASED; urgency=medium
 
-  * Fix regression in last release that crashes when using
+  * Fix bug in last release that crashes when using
     --all or running git-annex in a bare repository. May have also
     affected git-annex unused and git-annex info.
   * runshell: Use proot when running on Android, to work around
     Android 8's ill-advised seccomp filtering of system calls,
     including ones crucial for reliable thread locking.
     (This will only work with termux's version of proot.)
+  * Fix bug in last release that prevented the webapp opening on
+    non-Linux systems.
 
  -- Joey Hess <id@joeyh.name>  Tue, 08 May 2018 13:51:37 -0400
 

Utility/Android.hs

@@ -1,3 +1,5 @@
+{-# LANGUAGE CPP #-}
+
 {- Android stuff
  -
  - Copyright 2018 Joey Hess <id@joeyh.name>
@@ -14,4 +16,9 @@ import Common
 -- Note that this relies on termux's uname having been built with "Android"
 -- as the os name. Often on Android, uname will report "Linux".
 osAndroid :: IO Bool
-osAndroid = ("Android" `isPrefixOf` ) <$> readProcess "uname" ["-o"]
+#ifdef linux_HOST_OS
+osAndroid = catchDefaultIO False $
+	("Android" `isPrefixOf` ) <$> readProcess "uname" ["-o"]
+#else
+osAndroid = return False
+#endif

doc/bugs/can__39__t_launch_assistant_on_latest_OSX_build.mdwn

@@ -55,3 +55,5 @@ WebApp crashed: user error (uname ["-o"] exited 1)
 Yup! git-annex is great! Thanks for all your hard work on this project Joey!!
 
 —Andrew
+
+> [[fixed|done]] --[[Joey]]

doc/install/OSX/comment_23_895d4e837d05a318512730d66f14db22._comment

@@ -0,0 +1,11 @@
+[[!comment format=mdwn
+ username="joey"
+ subject="""comment 23"""
+ date="2018-05-08T18:03:05Z"
+ content="""
+Guys talking about uname -o and stuff, this is not the place to do that.
+File a [[bug]] report if you have a bug like that. You're making it harder
+for every person who opens this page to install git-annex and ends up
+wwading through discussion of fixed bugs like that one. Also, I respond
+*much* faster to bug reports than to random misplaced comments about bugs.
+"""]]