This seems to have randomly started a few days ago. It used to be fine to run fish shell from Ubuntu bash for Windows. But suddenly when I hit Tab for autocomplete, it barfs with:

The file "x86" is not executable by this user in command substitution called on standard input

Also, when I just type x86 it doesn't actually run a command, but it tells me:

The file "x86" is not executable by this user

However, which x86 outputs nothing.

Any clue what in the world could be going on here?

  • whats your pwd? are you on or evaluating a path to c:\program files (x86)\ ? bash is likely to parse that as multiple file names. windows should never have allowed whitespace in filenames... – Frank Thomas Nov 22 '17 at 19:36
  • Ah, it looks like ` /mnt/c/Program Files (x86)/NVIDIA Corporation/PhysX/Common` (among a few others) is on my PATH. Is there a way to either eliminate those, as they're not even remotely relevant for the subsystem.... I mean, I could manually set the PATH of course – Wayne Werner Nov 22 '17 at 21:50
up vote 2 down vote accepted

This was a bug present in fish and fixed in version 2.3.0 - if it is still present in later versions, a report would be greatly appreciated.

You can install a newer version from the Ubuntu PPA repositories if the version installed by apt-get is too old.

  • You r question solves the problem, mine just rambles :) – Vedant Nov 25 '17 at 3:16

The issue here is in completer_t::complete_cmd, which invokes expand_string. This is a very general function that expands things like wildcards, process expansion, variable expansion, etc.

It's surely wrong to do these expansions in the components of $PATH.

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