* gnu/build/activation.scm (activate-current-system): Honor
$GUIX_NEW_SYSTEM by default.
* guix/scripts/system.scm (switch-to-system): Set $GUIX_NEW_SYSTEM
before loading SCRIPT.
"Return the '--system' argument passed on the kernel command line."
(find-long-option "--system" (linux-command-line)))
-(define* (activate-current-system #:optional (system (boot-time-system)))
+(define* (activate-current-system
+ #:optional (system (or (getenv "GUIX_NEW_SYSTEM")
+ (boot-time-system))))
"Atomically make SYSTEM the current system."
+ ;; The 'GUIX_NEW_SYSTEM' environment variable is used as a way for 'guix
+ ;; system reconfigure' to pass the file name of the new system.
+
(format #t "making '~a' the current system...~%" system)
;; Atomically make SYSTEM current.
;; The activation script may change $PATH, among others, so protect
;; against that.
(return (save-environment-excursion
+ ;; Tell 'activate-current-system' what the new system is.
+ (setenv "GUIX_NEW_SYSTEM" system)
+
(primitive-load (derivation->output-path script))))
;; TODO: Run 'deco reload ...'.