): Change second argument to 'settings.set' to properly handle case where ARG is NULL.

Age	Commit message (Expand)	Author
2019-03-04	services: Use 'file-append' for user account shells....* gnu/services/cuirass.scm (cuirass-account): Use 'file-append' instead of #~(string-append #$shadow "/sbin/nologin"). * gnu/services/monitoring.scm (zabbix-server-account): Likewise. (zabbix-agent-account): Likewise. * gnu/services/rsync.scm (rsync-account): Likewise. * gnu/services/ssh.scm (%openssh-accounts): Likewise.	Ludovic Courtès
2017-09-23	gnu: Add rsync service....* doc/guix.texi (Networking Services): Add rsync service documentation. * gnu/services/rsync.scm (<rsync-configuration>): New file. * gnu/tests/rsync.scm: New file. * gnu/local.mk (GNU_SYSTEM_MODULES): Add new files. Signed-off-by: Christopher Baines <mail@cbaines.net>	Oleg Pykhalov
Ludovic Courtès
2020-11-29	Use substitute servers on the local network....* guix/scripts/discover.scm: New file. * Makefile.am (MODULES): Add it. * nix/nix-daemon/guix-daemon.cc (options): Add "discover" option, (parse-opt): parse it, (main): start "guix discover" process when the option is set. * guix/scripts/substitute.scm (%local-substitute-urls): New variable, (substitute-urls): add it. * gnu/services/base.scm (<guix-configuration>): Add "discover?" field, (guix-shepherd-service): honor it. * doc/guix.texi (Invoking guix-daemon): Document "discover" option, (Base Services): ditto.	Mathieu Othacehe