Steps to reproduce:
1. Use regular C-x C-f /ssh:remote:/path/on/remote. The remote machine is a
GNU Linux machine too.

2. Then open eshell using M-x eshell on the remote machine.

3. Type `top` in the eshell prompt. You see the following error in a *top*
buffer:

..: 1: exec: /ssh:remote:/bin/top: not found

Process /ssh:remote:/bin/top exited abnormally with code 127

Expected behavior:
Since /bin/top is present on the remote (which can be verified if you do
the same in M-x shell), I'd expect top to work there via eshell.

I've verified that top in eshell does work if the eshell is run on the
local machine (no ssh and tramp-mode).


In GNU Emacs 27.1 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.22.30,
cairo version 1.15.10)
 of 2020-08-26 built on lgw01-amd64-030
Repository revision: a2fc5f02361a34ff7322032ce027c8bc4cc3b25a
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.11906000
System Description: Ubuntu 18.04.5 LTS

Recent messages:
(no useful messages)

Configured using:
 'configure --prefix= --prefix=/snap/emacs/current/usr --with-xwidgets
 --with-x-toolkit=gtk3 --without-xaw3d --with-modules --with-cairo
 'CFLAGS= -isystem/build/emacs/parts/emacs/install/usr/include -O2'
 'CPPFLAGS= -isystem/build/emacs/parts/emacs/install/usr/include'
 'LDFLAGS= -L/build/emacs/parts/emacs/install/lib
 -L/build/emacs/parts/emacs/install/usr/lib
 -L/build/emacs/parts/emacs/install/lib/x86_64-linux-gnu
 -L/build/emacs/parts/emacs/install/usr/lib/x86_64-linux-gnu''

Configured features:
XPM JPEG TIFF GIF PNG RSVG CAIRO SOUND GPM DBUS GSETTINGS GLIB NOTIFY
INOTIFY ACL LIBSELINUX GNUTLS LIBXML2 FREETYPE HARFBUZZ M17N_FLT LIBOTF
ZLIB TOOLKIT_SCROLL_BARS GTK3 X11 XDBE XIM MODULES THREADS XWIDGETS
LIBSYSTEMD JSON PDUMPER LCMS2 GMP

Important settings:
  value of $LANG: en_US.UTF-8
  locale-coding-system: utf-8-unix

Major mode: Go

Minor modes in effect:
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  global-hl-line-mode: t
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  savehist-mode: t
  save-place-mode: t
  show-smartparens-global-mode: t
  show-smartparens-mode: t
  smartparens-mode: t
  global-auto-revert-mode: t
  delete-selection-mode: t
  prelude-mode: t
  shell-dirtrack-mode: t
  which-key-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  eldoc-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  size-indication-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Load-path shadows:
None found.

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