Subject: bug#58307: 29.0.50; Fix battery mode over TRAMP on *BSD

From: Manuel Giraud <[email-masked]>
Date: Thu, 06 Oct 2022 10:17:17 +0200

Thank you Stefan and Michael!

Here is an updated version.  My wording in the comment might not be
correct.  Best regards.
>From f9b1ee4df0280daab91a103fde4ee3a707d4224c Mon Sep 17 00:00:00 2001
From: Manuel Giraud <[email-masked]>
Date: Wed, 5 Oct 2022 15:59:14 +0200
Subject: [PATCH] Fix BSD battery mode over TRAMP (bug#58307)

* lisp/battery.el (battery--call-process-to-string): Simple wrapper
  to `call-process' that outputs to a string.
  (battery-bsd-apm): Use it instead of `shell-command-to-string'.
---
 lisp/battery.el | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/lisp/battery.el b/lisp/battery.el
index 72b3dfdae7..4c83f8a7d3 100644
--- a/lisp/battery.el
+++ b/lisp/battery.el
@@ -914,6 +914,15 @@ battery-upower
 
 ;;; `apm' interface for BSD.
 
+;; This function is a wrapper on `call-process' that return the
+;; standard output in a string.  We are using it instead
+;; `shell-command-to-string' because this last one is trying to run
+;; PROGRAM on the remote host if the buffer is remote.
+(defun battery--call-process-to-string (program &rest args)
+  (with-output-to-string
+    (with-current-buffer standard-output
+      (apply #'call-process program nil t nil args))))
+
 (defun battery-bsd-apm ()
   "Get APM status information from BSD apm binary.
 The following %-sequences are provided:
@@ -929,13 +938,14 @@ battery-bsd-apm
 %t Remaining time (to charge or discharge) in the form `h:min'"
   (let* ((os-name (car (split-string
                         ;; FIXME: Can't we use something like `system-type'?
-                        (shell-command-to-string "/usr/bin/uname"))))
+                        (battery--call-process-to-string (executable-find "uname")))))
          (apm-flag (pcase os-name
                      ("OpenBSD" "mP")
                      ("FreeBSD" "st")
                      (_         "ms")))
-         (apm-cmd (concat "/usr/sbin/apm -abl" apm-flag))
-         (apm-output (split-string (shell-command-to-string apm-cmd)))
+         (apm-args (concat "-abl" apm-flag))
+         (apm-output (split-string
+                      (battery--call-process-to-string (executable-find "apm") apm-args)))
          (indices (pcase os-name
                     ;; FreeBSD's manpage documents that multiple
                     ;; outputs are ordered by "the order in which
-- 
2.37.3

-- 
Manuel Giraud