pull upstream changes from gitstatus

gitstatus/gitstatus.plugin.zsh

@@ -412,11 +412,17 @@ function gitstatus_start() {
         echo -nE $'bye\x1f0\x1e'"
       local setsid=${commands[setsid]:-/usr/local/opt/util-linux/bin/setsid}
       [[ -x $setsid ]] && setsid=${(q)setsid} || setsid=
-      cmd="cd /; read; $setsid zsh -dfxc ${(q)cmd} &!; rm -f ${(q)req_fifo} ${(q)resp_fifo} ${(q)lock_file}"
+      # Try to use the same executable as the current zsh. Some people like having an ancient
+      # `zsh` in their PATH while using a newer version. zsh 5.0.2 hangs when enabling `monitor`.
+      #
+      #   zsh -mc '' &!  # hangs when using zsh 5.0.2
+      local zsh=${${:-/proc/self/exe}:A}
+      [[ -x $zsh ]] || zsh=zsh
+      cmd="cd /; read; $setsid $zsh -dfxc ${(q)cmd} &!; rm -f ${(q)req_fifo} ${(q)resp_fifo} ${(q)lock_file}"
       # We use `zsh -c` instead of plain {} or () to work around bugs in zplug (it hangs on
       # startup). Double fork is to daemonize, and so is `setsid`. Note that on macOS `setsid` has
       # to be installed manually by running  `brew install util-linux`.
-      zsh -dfmxc $cmd <$req_fifo >$log_file 2>&1 3<$lock_file 4>$resp_fifo &!
+      $zsh -dfmxc $cmd <$req_fifo >$log_file 2>&1 3<$lock_file 4>$resp_fifo &!
 
       sysopen -w -o cloexec,sync -u req_fd $req_fifo
       sysopen -r -o cloexec -u resp_fd $resp_fifo