Add s6-svdir-link and s6-svdir-unlink

 Not tested yet; not documented yet; to come soon.

Signed-off-by: Laurent Bercot <ska@appnovation.com>

14 files changed, 337 insertions, 156 deletions

diff --git a/.gitignore b/.gitignore
index 6084fce..c45d337 100644
--- a/.gitignore
+++ b/.gitignore
@@ -28,12 +28,15 @@
 /s6-svdt
 /s6-svdt-clear
 /s6-permafailon
+/s6-svdir-link
+/s6-svdir-unlink
 /s6-envdir
 /s6-envuidgid
 /s6-fghack
 /s6-log
 /s6-setlock
 /s6-setsid
+/s6-socklog
 /s6-softlimit
 /s6-tai64n
 /s6-tai64nlocal
diff --git a/doc/s6-socklog.html b/doc/s6-socklog.html
index d463fbb..3f66cdc 100644
--- a/doc/s6-socklog.html
+++ b/doc/s6-socklog.html
@@ -83,11 +83,11 @@ This allows <tt>s6-socklog</tt> to use the <a href="notifywhenup.html">s6
 mechanism to notify readiness</a>. <em>notif</em> cannot be lesser than 3.
 If this option is not given, no readiness notification is sent. </li>
  <li> <tt>-u&nbsp;<em>uid</em></tt>&nbsp;: drop user id to <em>uid</em> </li>
- <li> <tt>-g&nbsp;<em>gid</em></tt>&nbsp;: drop group ID to <em>gid</em> </li>
+ <li> <tt>-g&nbsp;<em>gid</em></tt>&nbsp;: drop group id to <em>gid</em> </li>
  <li> <tt>-G&nbsp;<em>gidlist</em></tt>&nbsp;: set supplementary group list
-to <em>gidlist</em>, which must be given as a comma-separated list of numeric GIDs,
+to <em>gidlist</em>, which must be given as a comma-separated list of numeric gids,
 without spaces. </li>
- <li> <tt>-U</tt>&nbsp;: set user ID, group ID and supplementary group list
+ <li> <tt>-U</tt>&nbsp;: set user id, group id and supplementary group list
 to the values of the UID, GID and GIDLIST environment variables. If a <tt>-u</tt>,
 <tt>-g</tt> or <tt>-G</tt> option is given after <tt>-U</tt>, the command line
 value overrides the environment variable. </li>
diff --git a/package/deps.mak b/package/deps.mak
index 2f21727..c2465d4 100644
--- a/package/deps.mak
+++ b/package/deps.mak
@@ -92,7 +92,8 @@ src/libs6/s6_fdholder_setdump.o src/libs6/s6_fdholder_setdump.lo: src/libs6/s6_f
 src/libs6/s6_fdholder_start.o src/libs6/s6_fdholder_start.lo: src/libs6/s6_fdholder_start.c src/include/s6/s6-fdholder.h
 src/libs6/s6_fdholder_store.o src/libs6/s6_fdholder_store.lo: src/libs6/s6_fdholder_store.c src/include/s6/s6-fdholder.h
 src/libs6/s6_fdholder_store_async.o src/libs6/s6_fdholder_store_async.lo: src/libs6/s6_fdholder_store_async.c src/include/s6/s6-fdholder.h
-src/libs6/s6_supervise_link.o src/libs6/s6_supervise_link.lo: src/libs6/s6_supervise_link.c src/include/s6/ftrigr.h src/include/s6/ftrigw.h src/include/s6/s6-supervise.h
+src/libs6/s6_supervise_link.o src/libs6/s6_supervise_link.lo: src/libs6/s6_supervise_link.c src/include/s6/s6-supervise.h
+src/libs6/s6_supervise_link_names.o src/libs6/s6_supervise_link_names.lo: src/libs6/s6_supervise_link_names.c src/include/s6/ftrigr.h src/include/s6/ftrigw.h src/include/s6/s6-supervise.h
 src/libs6/s6_supervise_unlink.o src/libs6/s6_supervise_unlink.lo: src/libs6/s6_supervise_unlink.c src/include/s6/s6-supervise.h
 src/libs6/s6_svc_ok.o src/libs6/s6_svc_ok.lo: src/libs6/s6_svc_ok.c src/include/s6/s6-supervise.h
 src/libs6/s6_svc_write.o src/libs6/s6_svc_write.lo: src/libs6/s6_svc_write.c src/include/s6/s6-supervise.h
@@ -124,6 +125,8 @@ src/supervision/s6-notifyoncheck.o src/supervision/s6-notifyoncheck.lo: src/supe
 src/supervision/s6-permafailon.o src/supervision/s6-permafailon.lo: src/supervision/s6-permafailon.c src/include/s6/s6-supervise.h
 src/supervision/s6-supervise.o src/supervision/s6-supervise.lo: src/supervision/s6-supervise.c src/include/s6/ftrigw.h src/include/s6/s6-supervise.h
 src/supervision/s6-svc.o src/supervision/s6-svc.lo: src/supervision/s6-svc.c src/include/s6/config.h src/include/s6/s6-supervise.h
+src/supervision/s6-svdir-link.o src/supervision/s6-svdir-link.lo: src/supervision/s6-svdir-link.c src/include/s6/s6-supervise.h
+src/supervision/s6-svdir-unlink.o src/supervision/s6-svdir-unlink.lo: src/supervision/s6-svdir-unlink.c src/include/s6/s6-supervise.h
 src/supervision/s6-svdt-clear.o src/supervision/s6-svdt-clear.lo: src/supervision/s6-svdt-clear.c src/include/s6/s6-supervise.h
 src/supervision/s6-svdt.o src/supervision/s6-svdt.lo: src/supervision/s6-svdt.c src/include/s6/s6-supervise.h
 src/supervision/s6-svlisten.o src/supervision/s6-svlisten.lo: src/supervision/s6-svlisten.c src/supervision/s6-svlisten.h src/include/s6/compat.h
@@ -207,12 +210,12 @@ s6-fdholder-transferdump: src/fdholder/s6-fdholder-transferdump.o ${LIBS6}
 s6-fdholderd: EXTRA_LIBS := -lskarnet ${SOCKET_LIB} ${SYSCLOCK_LIB}
 s6-fdholderd: src/fdholder/s6-fdholderd.o ${LIBS6}
 ifeq ($(strip $(STATIC_LIBS_ARE_PIC)),)
-libs6.a.xyzzy: src/libs6/ftrigr1_zero.o src/libs6/ftrigr_check.o src/libs6/ftrigr_checksa.o src/libs6/ftrigr_ack.o src/libs6/ftrigr_end.o src/libs6/ftrigr_start.o src/libs6/ftrigr_startf.o src/libs6/ftrigr_subscribe.o src/libs6/ftrigr_unsubscribe.o src/libs6/ftrigr_update.o src/libs6/ftrigr_updateb.o src/libs6/ftrigr_wait_and.o src/libs6/ftrigr_wait_or.o src/libs6/ftrigr_zero.o src/libs6/ftrigw_clean.o src/libs6/ftrigw_fifodir_make.o src/libs6/ftrigw_notify.o src/libs6/ftrigw_notifyb.o src/libs6/ftrigw_notifyb_nosig.o src/libs6/s6_accessrules_backend_cdb.o src/libs6/s6_accessrules_backend_fs.o src/libs6/s6_accessrules_keycheck_ip4.o src/libs6/s6_accessrules_keycheck_ip6.o src/libs6/s6_accessrules_keycheck_reversedns.o src/libs6/s6_accessrules_keycheck_uidgid.o src/libs6/s6_accessrules_params_free.o src/libs6/s6_accessrules_uidgid_cdb.o src/libs6/s6_accessrules_uidgid_fs.o src/libs6/s6_compat_el_semicolon.o src/libs6/s6_dtally_pack.o src/libs6/s6_dtally_unpack.o src/libs6/s6_dtally_read.o src/libs6/s6_dtally_write.o src/libs6/s6_svc_ok.o src/libs6/s6_svc_write.o src/libs6/s6_svc_writectl.o src/libs6/s6_svstatus_pack.o src/libs6/s6_svstatus_read.o src/libs6/s6_svstatus_unpack.o src/libs6/s6_svstatus_write.o src/libs6/s6lock_acquire.o src/libs6/s6lock_check.o src/libs6/s6lock_end.o src/libs6/s6lock_release.o src/libs6/s6lock_start.o src/libs6/s6lock_startf.o src/libs6/s6lock_update.o src/libs6/s6lock_wait_and.o src/libs6/s6lock_wait_or.o src/libs6/s6lock_zero.o src/libs6/s6_fdholder_delete.o src/libs6/s6_fdholder_delete_async.o src/libs6/s6_fdholder_end.o src/libs6/s6_fdholder_getdump.o src/libs6/s6_fdholder_list.o src/libs6/s6_fdholder_list_async.o src/libs6/s6_fdholder_list_cb.o src/libs6/s6_fdholder_retrieve.o src/libs6/s6_fdholder_retrieve_async.o src/libs6/s6_fdholder_retrieve_cb.o src/libs6/s6_fdholder_setdump.o src/libs6/s6_fdholder_start.o src/libs6/s6_fdholder_store.o src/libs6/s6_fdholder_store_async.o src/libs6/s6_supervise_link.o src/libs6/s6_supervise_unlink.o
+libs6.a.xyzzy: src/libs6/ftrigr1_zero.o src/libs6/ftrigr_check.o src/libs6/ftrigr_checksa.o src/libs6/ftrigr_ack.o src/libs6/ftrigr_end.o src/libs6/ftrigr_start.o src/libs6/ftrigr_startf.o src/libs6/ftrigr_subscribe.o src/libs6/ftrigr_unsubscribe.o src/libs6/ftrigr_update.o src/libs6/ftrigr_updateb.o src/libs6/ftrigr_wait_and.o src/libs6/ftrigr_wait_or.o src/libs6/ftrigr_zero.o src/libs6/ftrigw_clean.o src/libs6/ftrigw_fifodir_make.o src/libs6/ftrigw_notify.o src/libs6/ftrigw_notifyb.o src/libs6/ftrigw_notifyb_nosig.o src/libs6/s6_accessrules_backend_cdb.o src/libs6/s6_accessrules_backend_fs.o src/libs6/s6_accessrules_keycheck_ip4.o src/libs6/s6_accessrules_keycheck_ip6.o src/libs6/s6_accessrules_keycheck_reversedns.o src/libs6/s6_accessrules_keycheck_uidgid.o src/libs6/s6_accessrules_params_free.o src/libs6/s6_accessrules_uidgid_cdb.o src/libs6/s6_accessrules_uidgid_fs.o src/libs6/s6_compat_el_semicolon.o src/libs6/s6_dtally_pack.o src/libs6/s6_dtally_unpack.o src/libs6/s6_dtally_read.o src/libs6/s6_dtally_write.o src/libs6/s6_svc_ok.o src/libs6/s6_svc_write.o src/libs6/s6_svc_writectl.o src/libs6/s6_svstatus_pack.o src/libs6/s6_svstatus_read.o src/libs6/s6_svstatus_unpack.o src/libs6/s6_svstatus_write.o src/libs6/s6lock_acquire.o src/libs6/s6lock_check.o src/libs6/s6lock_end.o src/libs6/s6lock_release.o src/libs6/s6lock_start.o src/libs6/s6lock_startf.o src/libs6/s6lock_update.o src/libs6/s6lock_wait_and.o src/libs6/s6lock_wait_or.o src/libs6/s6lock_zero.o src/libs6/s6_fdholder_delete.o src/libs6/s6_fdholder_delete_async.o src/libs6/s6_fdholder_end.o src/libs6/s6_fdholder_getdump.o src/libs6/s6_fdholder_list.o src/libs6/s6_fdholder_list_async.o src/libs6/s6_fdholder_list_cb.o src/libs6/s6_fdholder_retrieve.o src/libs6/s6_fdholder_retrieve_async.o src/libs6/s6_fdholder_retrieve_cb.o src/libs6/s6_fdholder_setdump.o src/libs6/s6_fdholder_start.o src/libs6/s6_fdholder_store.o src/libs6/s6_fdholder_store_async.o src/libs6/s6_supervise_link.o src/libs6/s6_supervise_link_names.o src/libs6/s6_supervise_unlink.o
 else
-libs6.a.xyzzy: src/libs6/ftrigr1_zero.lo src/libs6/ftrigr_check.lo src/libs6/ftrigr_checksa.lo src/libs6/ftrigr_ack.lo src/libs6/ftrigr_end.lo src/libs6/ftrigr_start.lo src/libs6/ftrigr_startf.lo src/libs6/ftrigr_subscribe.lo src/libs6/ftrigr_unsubscribe.lo src/libs6/ftrigr_update.lo src/libs6/ftrigr_updateb.lo src/libs6/ftrigr_wait_and.lo src/libs6/ftrigr_wait_or.lo src/libs6/ftrigr_zero.lo src/libs6/ftrigw_clean.lo src/libs6/ftrigw_fifodir_make.lo src/libs6/ftrigw_notify.lo src/libs6/ftrigw_notifyb.lo src/libs6/ftrigw_notifyb_nosig.lo src/libs6/s6_accessrules_backend_cdb.lo src/libs6/s6_accessrules_backend_fs.lo src/libs6/s6_accessrules_keycheck_ip4.lo src/libs6/s6_accessrules_keycheck_ip6.lo src/libs6/s6_accessrules_keycheck_reversedns.lo src/libs6/s6_accessrules_keycheck_uidgid.lo src/libs6/s6_accessrules_params_free.lo src/libs6/s6_accessrules_uidgid_cdb.lo src/libs6/s6_accessrules_uidgid_fs.lo src/libs6/s6_compat_el_semicolon.lo src/libs6/s6_dtally_pack.lo src/libs6/s6_dtally_unpack.lo src/libs6/s6_dtally_read.lo src/libs6/s6_dtally_write.lo src/libs6/s6_svc_ok.lo src/libs6/s6_svc_write.lo src/libs6/s6_svc_writectl.lo src/libs6/s6_svstatus_pack.lo src/libs6/s6_svstatus_read.lo src/libs6/s6_svstatus_unpack.lo src/libs6/s6_svstatus_write.lo src/libs6/s6lock_acquire.lo src/libs6/s6lock_check.lo src/libs6/s6lock_end.lo src/libs6/s6lock_release.lo src/libs6/s6lock_start.lo src/libs6/s6lock_startf.lo src/libs6/s6lock_update.lo src/libs6/s6lock_wait_and.lo src/libs6/s6lock_wait_or.lo src/libs6/s6lock_zero.lo src/libs6/s6_fdholder_delete.lo src/libs6/s6_fdholder_delete_async.lo src/libs6/s6_fdholder_end.lo src/libs6/s6_fdholder_getdump.lo src/libs6/s6_fdholder_list.lo src/libs6/s6_fdholder_list_async.lo src/libs6/s6_fdholder_list_cb.lo src/libs6/s6_fdholder_retrieve.lo src/libs6/s6_fdholder_retrieve_async.lo src/libs6/s6_fdholder_retrieve_cb.lo src/libs6/s6_fdholder_setdump.lo src/libs6/s6_fdholder_start.lo src/libs6/s6_fdholder_store.lo src/libs6/s6_fdholder_store_async.lo src/libs6/s6_supervise_link.lo src/libs6/s6_supervise_unlink.lo
+libs6.a.xyzzy: src/libs6/ftrigr1_zero.lo src/libs6/ftrigr_check.lo src/libs6/ftrigr_checksa.lo src/libs6/ftrigr_ack.lo src/libs6/ftrigr_end.lo src/libs6/ftrigr_start.lo src/libs6/ftrigr_startf.lo src/libs6/ftrigr_subscribe.lo src/libs6/ftrigr_unsubscribe.lo src/libs6/ftrigr_update.lo src/libs6/ftrigr_updateb.lo src/libs6/ftrigr_wait_and.lo src/libs6/ftrigr_wait_or.lo src/libs6/ftrigr_zero.lo src/libs6/ftrigw_clean.lo src/libs6/ftrigw_fifodir_make.lo src/libs6/ftrigw_notify.lo src/libs6/ftrigw_notifyb.lo src/libs6/ftrigw_notifyb_nosig.lo src/libs6/s6_accessrules_backend_cdb.lo src/libs6/s6_accessrules_backend_fs.lo src/libs6/s6_accessrules_keycheck_ip4.lo src/libs6/s6_accessrules_keycheck_ip6.lo src/libs6/s6_accessrules_keycheck_reversedns.lo src/libs6/s6_accessrules_keycheck_uidgid.lo src/libs6/s6_accessrules_params_free.lo src/libs6/s6_accessrules_uidgid_cdb.lo src/libs6/s6_accessrules_uidgid_fs.lo src/libs6/s6_compat_el_semicolon.lo src/libs6/s6_dtally_pack.lo src/libs6/s6_dtally_unpack.lo src/libs6/s6_dtally_read.lo src/libs6/s6_dtally_write.lo src/libs6/s6_svc_ok.lo src/libs6/s6_svc_write.lo src/libs6/s6_svc_writectl.lo src/libs6/s6_svstatus_pack.lo src/libs6/s6_svstatus_read.lo src/libs6/s6_svstatus_unpack.lo src/libs6/s6_svstatus_write.lo src/libs6/s6lock_acquire.lo src/libs6/s6lock_check.lo src/libs6/s6lock_end.lo src/libs6/s6lock_release.lo src/libs6/s6lock_start.lo src/libs6/s6lock_startf.lo src/libs6/s6lock_update.lo src/libs6/s6lock_wait_and.lo src/libs6/s6lock_wait_or.lo src/libs6/s6lock_zero.lo src/libs6/s6_fdholder_delete.lo src/libs6/s6_fdholder_delete_async.lo src/libs6/s6_fdholder_end.lo src/libs6/s6_fdholder_getdump.lo src/libs6/s6_fdholder_list.lo src/libs6/s6_fdholder_list_async.lo src/libs6/s6_fdholder_list_cb.lo src/libs6/s6_fdholder_retrieve.lo src/libs6/s6_fdholder_retrieve_async.lo src/libs6/s6_fdholder_retrieve_cb.lo src/libs6/s6_fdholder_setdump.lo src/libs6/s6_fdholder_start.lo src/libs6/s6_fdholder_store.lo src/libs6/s6_fdholder_store_async.lo src/libs6/s6_supervise_link.lo src/libs6/s6_supervise_link_names.lo src/libs6/s6_supervise_unlink.lo
 endif
 libs6.so.xyzzy: EXTRA_LIBS := -lskarnet
-libs6.so.xyzzy: src/libs6/ftrigr1_zero.lo src/libs6/ftrigr_check.lo src/libs6/ftrigr_checksa.lo src/libs6/ftrigr_ack.lo src/libs6/ftrigr_end.lo src/libs6/ftrigr_start.lo src/libs6/ftrigr_startf.lo src/libs6/ftrigr_subscribe.lo src/libs6/ftrigr_unsubscribe.lo src/libs6/ftrigr_update.lo src/libs6/ftrigr_updateb.lo src/libs6/ftrigr_wait_and.lo src/libs6/ftrigr_wait_or.lo src/libs6/ftrigr_zero.lo src/libs6/ftrigw_clean.lo src/libs6/ftrigw_fifodir_make.lo src/libs6/ftrigw_notify.lo src/libs6/ftrigw_notifyb.lo src/libs6/ftrigw_notifyb_nosig.lo src/libs6/s6_accessrules_backend_cdb.lo src/libs6/s6_accessrules_backend_fs.lo src/libs6/s6_accessrules_keycheck_ip4.lo src/libs6/s6_accessrules_keycheck_ip6.lo src/libs6/s6_accessrules_keycheck_reversedns.lo src/libs6/s6_accessrules_keycheck_uidgid.lo src/libs6/s6_accessrules_params_free.lo src/libs6/s6_accessrules_uidgid_cdb.lo src/libs6/s6_accessrules_uidgid_fs.lo src/libs6/s6_compat_el_semicolon.lo src/libs6/s6_dtally_pack.lo src/libs6/s6_dtally_unpack.lo src/libs6/s6_dtally_read.lo src/libs6/s6_dtally_write.lo src/libs6/s6_svc_ok.lo src/libs6/s6_svc_write.lo src/libs6/s6_svc_writectl.lo src/libs6/s6_svstatus_pack.lo src/libs6/s6_svstatus_read.lo src/libs6/s6_svstatus_unpack.lo src/libs6/s6_svstatus_write.lo src/libs6/s6lock_acquire.lo src/libs6/s6lock_check.lo src/libs6/s6lock_end.lo src/libs6/s6lock_release.lo src/libs6/s6lock_start.lo src/libs6/s6lock_startf.lo src/libs6/s6lock_update.lo src/libs6/s6lock_wait_and.lo src/libs6/s6lock_wait_or.lo src/libs6/s6lock_zero.lo src/libs6/s6_fdholder_delete.lo src/libs6/s6_fdholder_delete_async.lo src/libs6/s6_fdholder_end.lo src/libs6/s6_fdholder_getdump.lo src/libs6/s6_fdholder_list.lo src/libs6/s6_fdholder_list_async.lo src/libs6/s6_fdholder_list_cb.lo src/libs6/s6_fdholder_retrieve.lo src/libs6/s6_fdholder_retrieve_async.lo src/libs6/s6_fdholder_retrieve_cb.lo src/libs6/s6_fdholder_setdump.lo src/libs6/s6_fdholder_start.lo src/libs6/s6_fdholder_store.lo src/libs6/s6_fdholder_store_async.lo src/libs6/s6_supervise_link.lo src/libs6/s6_supervise_unlink.lo
+libs6.so.xyzzy: src/libs6/ftrigr1_zero.lo src/libs6/ftrigr_check.lo src/libs6/ftrigr_checksa.lo src/libs6/ftrigr_ack.lo src/libs6/ftrigr_end.lo src/libs6/ftrigr_start.lo src/libs6/ftrigr_startf.lo src/libs6/ftrigr_subscribe.lo src/libs6/ftrigr_unsubscribe.lo src/libs6/ftrigr_update.lo src/libs6/ftrigr_updateb.lo src/libs6/ftrigr_wait_and.lo src/libs6/ftrigr_wait_or.lo src/libs6/ftrigr_zero.lo src/libs6/ftrigw_clean.lo src/libs6/ftrigw_fifodir_make.lo src/libs6/ftrigw_notify.lo src/libs6/ftrigw_notifyb.lo src/libs6/ftrigw_notifyb_nosig.lo src/libs6/s6_accessrules_backend_cdb.lo src/libs6/s6_accessrules_backend_fs.lo src/libs6/s6_accessrules_keycheck_ip4.lo src/libs6/s6_accessrules_keycheck_ip6.lo src/libs6/s6_accessrules_keycheck_reversedns.lo src/libs6/s6_accessrules_keycheck_uidgid.lo src/libs6/s6_accessrules_params_free.lo src/libs6/s6_accessrules_uidgid_cdb.lo src/libs6/s6_accessrules_uidgid_fs.lo src/libs6/s6_compat_el_semicolon.lo src/libs6/s6_dtally_pack.lo src/libs6/s6_dtally_unpack.lo src/libs6/s6_dtally_read.lo src/libs6/s6_dtally_write.lo src/libs6/s6_svc_ok.lo src/libs6/s6_svc_write.lo src/libs6/s6_svc_writectl.lo src/libs6/s6_svstatus_pack.lo src/libs6/s6_svstatus_read.lo src/libs6/s6_svstatus_unpack.lo src/libs6/s6_svstatus_write.lo src/libs6/s6lock_acquire.lo src/libs6/s6lock_check.lo src/libs6/s6lock_end.lo src/libs6/s6lock_release.lo src/libs6/s6lock_start.lo src/libs6/s6lock_startf.lo src/libs6/s6lock_update.lo src/libs6/s6lock_wait_and.lo src/libs6/s6lock_wait_or.lo src/libs6/s6lock_zero.lo src/libs6/s6_fdholder_delete.lo src/libs6/s6_fdholder_delete_async.lo src/libs6/s6_fdholder_end.lo src/libs6/s6_fdholder_getdump.lo src/libs6/s6_fdholder_list.lo src/libs6/s6_fdholder_list_async.lo src/libs6/s6_fdholder_list_cb.lo src/libs6/s6_fdholder_retrieve.lo src/libs6/s6_fdholder_retrieve_async.lo src/libs6/s6_fdholder_retrieve_cb.lo src/libs6/s6_fdholder_setdump.lo src/libs6/s6_fdholder_start.lo src/libs6/s6_fdholder_store.lo src/libs6/s6_fdholder_store_async.lo src/libs6/s6_supervise_link.lo src/libs6/s6_supervise_link_names.lo src/libs6/s6_supervise_unlink.lo
 ifeq ($(strip $(STATIC_LIBS_ARE_PIC)),)
 libs6lockd.a.xyzzy: src/libs6/s6lockd_openandlock.o
 else
@@ -244,6 +247,10 @@ s6-supervise: EXTRA_LIBS := -lskarnet ${SYSCLOCK_LIB}
 s6-supervise: src/supervision/s6-supervise.o libs6.a.xyzzy
 s6-svc: EXTRA_LIBS := -lskarnet
 s6-svc: src/supervision/s6-svc.o ${LIBS6}
+s6-svdir-link: EXTRA_LIBS := -lskarnet ${SOCKET_LIB} ${SYSCLOCK_LIB} ${SPAWN_LIB}
+s6-svdir-link: src/supervision/s6-svdir-link.o ${LIBS6}
+s6-svdir-unlink: EXTRA_LIBS := -lskarnet
+s6-svdir-unlink: src/supervision/s6-svdir-unlink.o ${LIBS6}
 s6-svdt: EXTRA_LIBS := -lskarnet
 s6-svdt: src/supervision/s6-svdt.o ${LIBS6}
 s6-svdt-clear: EXTRA_LIBS := -lskarnet
diff --git a/package/modes b/package/modes
index 4678bec..51947c2 100644
--- a/package/modes
+++ b/package/modes
@@ -11,6 +11,8 @@ s6-mkfifodir			0755
 s6-svscan			0755
 s6-supervise			0755
 s6-svc				0755
+s6-svdir-link			0755
+s6-svdir-unlink			0755
 s6-svscanctl			0755
 s6-svok				0755
 s6-svstat			0755
diff --git a/package/targets.mak b/package/targets.mak
index 0f1ebab..5516cf9 100644
--- a/package/targets.mak
+++ b/package/targets.mak
@@ -11,6 +11,8 @@ s6-mkfifodir \
 s6-svscan \
 s6-supervise \
 s6-svc \
+s6-svdir-link \
+s6-svdir-unlink \
 s6-svscanctl \
 s6-svok \
 s6-svstat \
diff --git a/src/include/s6/s6-supervise.h b/src/include/s6/s6-supervise.h
index 9375bec..c0dc1b6 100644
--- a/src/include/s6/s6-supervise.h
+++ b/src/include/s6/s6-supervise.h
@@ -57,6 +57,8 @@ extern int s6_svstatus_write (char const *, s6_svstatus_t const *) ;
 
 extern int s6_supervise_link (char const *, char const *const *, size_t, char const *, uint32_t, tain const *, tain *) ;
 #define s6_supervise_link_g(scdir, servicedirs, n, prefix, options, deadline) s6_supervise_link(scdir, servicedirs, n, prefix, options, (deadline), &STAMP)
+extern int s6_supervise_link_names (char const *, char const *const *, char const *const *, size_t, uint32_t, tain const *, tain *) ;
+#define s6_supervise_link_names_g(scdir, servicedirs, names, n, options, deadline) s6_supervise_link_names(scdir, servicedirs, names, n, options, (deadline), &STAMP)
 extern void s6_supervise_unlink (char const *, char const *, uint32_t) ;
 
 typedef struct s6_dtally_s s6_dtally_t, *s6_dtally_ref ;
diff --git a/src/libs6/deps-lib/s6 b/src/libs6/deps-lib/s6
index 45e6c33..94eab87 100644
--- a/src/libs6/deps-lib/s6
+++ b/src/libs6/deps-lib/s6
@@ -63,5 +63,6 @@ s6_fdholder_start.o
 s6_fdholder_store.o
 s6_fdholder_store_async.o
 s6_supervise_link.o
+s6_supervise_link_names.o
 s6_supervise_unlink.o
 -lskarnet
diff --git a/src/libs6/s6_supervise_link.c b/src/libs6/s6_supervise_link.c
index 1d2ae15..0c6852c 100644
--- a/src/libs6/s6_supervise_link.c
+++ b/src/libs6/s6_supervise_link.c
@@ -1,156 +1,34 @@
 /* ISC license. */
 
-#include <stdint.h>
 #include <string.h>
-#include <unistd.h>
-#include <libgen.h>
-#include <errno.h>
-#include <sys/stat.h>
 
-#include <skalibs/bitarray.h>
-#include <skalibs/tai.h>
 #include <skalibs/stralloc.h>
 #include <skalibs/djbunix.h>
 
-#include <s6/ftrigr.h>
-#include <s6/ftrigw.h>
 #include <s6/s6-supervise.h>
 
-static inline void do_unlink (char const *scdir, char const *prefix, size_t prefixlen, size_t maxlen, char const *names, size_t nameslen, uint32_t killopts)
-{
-  char fn[prefixlen + maxlen + 1] ;
-  memcpy(fn, prefix, prefixlen) ;
-  while (nameslen)
-  {
-    size_t len = strlen(names) + 1 ;
-    memcpy(fn + prefixlen, names, len) ;
-    s6_supervise_unlink(scdir, fn, killopts) ;
-    names += len ; nameslen -= len ;
-  }
-}
-
-static uint16_t registerit (ftrigr_t *a, char *fn, size_t len, gid_t gid, uint32_t options, tain const *deadline, tain *stamp)
-{
-  if (options & 4)
-  {
-    int fd ;
-    memcpy(fn + len, "/down", 6) ;
-    fd = open_trunc(fn) ;
-    if (fd < 0) return 0 ;
-    fd_close(fd) ;
-  }
-  memcpy(fn + len, "/" S6_SUPERVISE_EVENTDIR, 1 + sizeof(S6_SUPERVISE_EVENTDIR)) ;
-  if (!ftrigw_fifodir_make(fn, gid, options & 1)) return 0 ;
-  return ftrigr_subscribe(a, fn, "s", 0, deadline, stamp) ;
-}
-
 int s6_supervise_link (char const *scdir, char const *const *servicedirs, size_t n, char const *prefix, uint32_t options, tain const *deadline, tain *stamp)
 {
-  size_t maxlen = 0 ;
-  size_t ntotal = n ;
-  unsigned char locked[bitarray_div8(n)] ;
-  unsigned char logged[bitarray_div8(n)] ;
-  if (!n) return 0 ;
-  memset(locked, 0, bitarray_div8(n)) ;
-  memset(logged, 0, bitarray_div8(n)) ;
-
-  for (size_t i = 0 ; i < n ; i++)
+  int r ;
+  size_t prefixlen = strlen(prefix) ;
+  stralloc sa = STRALLOC_ZERO ;
+  char const *names[n ? n : 1] ;
   {
-    struct stat st ;
-    size_t len = strlen(servicedirs[i]) ;
-    int h ;
-    char subdir[len + 5] ;
-    if (len > maxlen) maxlen = len ;
-    h = s6_svc_ok(servicedirs[i]) ;
-    if (h < 0) return -1 ;
-    if (h) bitarray_set(locked, i) ;
-    memcpy(subdir, servicedirs[i], len) ;
-    memcpy(subdir + len, "/log", 5) ;
-    if (stat(subdir, &st) < 0)
-    {
-      if (errno != ENOENT) return -1 ;
-    }
-    else
+    size_t indices[n ? n : 1] ;
+    for (size_t i = 0 ; i < n ; i++)
     {
-      int r ;
-      if (!S_ISDIR(st.st_mode)) return (errno = ENOTDIR, -1) ;
-      r = s6_svc_ok(subdir) ;
-      if (r < 0) return -1 ;
-      if (r != h) return (errno = EINVAL, -1) ;
-      bitarray_set(logged, i) ;
-      ntotal++ ;
+      indices[i] = sa.len ;
+      if (!stralloc_catb(&sa, prefix, prefixlen)
+       || !sabasename(&sa, servicedirs[i], strlen(servicedirs[i]))
+       || !stralloc_0(&sa)) goto err ;
     }
-  } 
-
-  {
-    stralloc lnames = STRALLOC_ZERO ;
-    ftrigr_t a = FTRIGR_ZERO ;
-    stralloc rpsa = STRALLOC_ZERO ;
-    gid_t gid = options & 2 ? -1 : getegid() ;
-    size_t scdirlen = strlen(scdir) ;
-    size_t prefixlen = strlen(prefix) ;
-    unsigned int m = 0 ;
-    size_t i = 0 ;
-    size_t lstart = 0 ;
-    uint32_t killopts = 0 ;
-    int r ;
-    uint16_t ids[ntotal] ;
-    char lname[scdirlen + prefixlen + maxlen + 2] ;
-    char fn[maxlen + 5 + (sizeof(S6_SUPERVISE_EVENTDIR) > 5 ? sizeof(S6_SUPERVISE_EVENTDIR) : 5)] ;
-    if (!ftrigr_startf(&a, deadline, stamp)) return -1 ;
-    memcpy(lname, scdir, scdirlen) ;
-    lname[scdirlen] = '/' ;
-    memcpy(lname + scdirlen + 1, prefix, prefixlen) ;
-    for (i = 0 ; i < n ; i++)
-    {
-      char *p ;
-      char const *src ;
-      size_t len = strlen(servicedirs[i]) ;
-      int h = bitarray_peek(locked, i) ;
-      memcpy(fn, servicedirs[i], len) ;
-      if (!h)
-      {
-        ids[m] = registerit(&a, fn, len, gid, options, deadline, stamp) ;
-        if (!ids[m++]) goto err ;
-        if (bitarray_peek(logged, i))
-        {
-          memcpy(fn + len, "/log", 4) ;
-          ids[m] = registerit(&a, fn, len + 4, gid, options, deadline, stamp) ;
-          if (!ids[m++]) goto err ;
-        }
-      }
-      fn[len] = 0 ;
-      p = basename(fn) ;
-      len = strlen(p) ;
-      memcpy(lname + scdirlen + 1 + prefixlen, p, len + 1) ;
-      lstart = lnames.len ;
-      if (!h && !stralloc_catb(&lnames, p, len + 1)) goto err ;
-      if (servicedirs[i][0] == '/') src = servicedirs[i] ;
-      else
-      {
-        rpsa.len = 0 ;
-        if (sarealpath(&rpsa, servicedirs[i]) < 0 || !stralloc_0(&rpsa)) goto errl ;
-        src = rpsa.s ;
-      }
-      if (symlink(src, lname) < 0 && (!h || errno != EEXIST)) goto errl ;
-    }
-    stralloc_free(&rpsa) ;
-    r = s6_svc_writectl(scdir, S6_SVSCAN_CTLDIR, "a", 1) ;
-    if (r <= 0) goto errsa ;
-    killopts = 3 ;
-    if (ftrigr_wait_and(&a, ids, m, deadline, stamp) < 0) goto errsa ;
-    ftrigr_end(&a) ;
-    stralloc_free(&lnames) ;
-    return m ;
-
-   errl:
-    lnames.len = lstart ;
-   err:
-    stralloc_free(&rpsa) ;
-   errsa:
-    ftrigr_end(&a) ;
-    do_unlink(scdir, prefix, prefixlen, maxlen, lnames.s, lnames.len, killopts | (options & 4)) ;
-    stralloc_free(&lnames) ;
-    return -1 ;
+    for (size_t i = 0 ; i < n ; i++) names[i] = sa.s + indices[i] ;
   }
+  r = s6_supervise_link_names(scdir, servicedirs, names, n, options, deadline, stamp) ;
+  stralloc_free(&sa) ;
+  return r ;
+
+ err:
+  stralloc_free(&sa) ;
+  return -1 ;
 }
diff --git a/src/libs6/s6_supervise_link_names.c b/src/libs6/s6_supervise_link_names.c
new file mode 100644
index 0000000..8cba399
--- /dev/null
+++ b/src/libs6/s6_supervise_link_names.c
@@ -0,0 +1,136 @@
+/* ISC license. */
+
+#include <stdint.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sys/stat.h>
+
+#include <skalibs/bitarray.h>
+#include <skalibs/tai.h>
+#include <skalibs/stralloc.h>
+#include <skalibs/djbunix.h>
+
+#include <s6/ftrigr.h>
+#include <s6/ftrigw.h>
+#include <s6/s6-supervise.h>
+
+static inline void do_unlink (char const *scdir, char const *const *names, size_t n, uint32_t killopts)
+{
+  for (size_t i = 0 ; i < n ; i++)
+    s6_supervise_unlink(scdir, names[i], killopts) ;
+}
+
+static uint16_t registerit (ftrigr_t *a, char *fn, size_t len, gid_t gid, uint32_t options, tain const *deadline, tain *stamp)
+{
+  if (options & 4)
+  {
+    int fd ;
+    memcpy(fn + len, "/down", 6) ;
+    fd = open_trunc(fn) ;
+    if (fd < 0) return 0 ;
+    fd_close(fd) ;
+  }
+  memcpy(fn + len, "/" S6_SUPERVISE_EVENTDIR, 1 + sizeof(S6_SUPERVISE_EVENTDIR)) ;
+  if (!ftrigw_fifodir_make(fn, gid, options & 1)) return 0 ;
+  return ftrigr_subscribe(a, fn, "s", 0, deadline, stamp) ;
+}
+
+int s6_supervise_link_names (char const *scdir, char const *const *servicedirs, char const *const *names, size_t n, uint32_t options, tain const *deadline, tain *stamp)
+{
+  size_t maxnlen = 0, maxlen = 0 ;
+  size_t ntotal = n ;
+  unsigned char locked[bitarray_div8(n)] ;
+  unsigned char logged[bitarray_div8(n)] ;
+  if (!n) return 0 ;
+  memset(locked, 0, bitarray_div8(n)) ;
+  memset(logged, 0, bitarray_div8(n)) ;
+
+  for (size_t i = 0 ; i < n ; i++)
+  {
+    struct stat st ;
+    size_t len = strlen(servicedirs[i]) ;
+    size_t nlen = strlen(names[i]) ;
+    int h ;
+    char subdir[len + 5] ;
+    if (nlen > maxnlen) maxnlen = nlen ;
+    if (len > maxlen) maxlen = nlen ;
+    h = s6_svc_ok(servicedirs[i]) ;
+    if (h < 0) return -1 ;
+    if (h) bitarray_set(locked, i) ;
+    memcpy(subdir, servicedirs[i], len) ;
+    memcpy(subdir + len, "/log", 5) ;
+    if (stat(subdir, &st) < 0)
+    {
+      if (errno != ENOENT) return -1 ;
+    }
+    else
+    {
+      int r ;
+      if (!S_ISDIR(st.st_mode)) return (errno = ENOTDIR, -1) ;
+      r = s6_svc_ok(subdir) ;
+      if (r < 0) return -1 ;
+      if (r != h) return (errno = EINVAL, -1) ;
+      bitarray_set(logged, i) ;
+      ntotal++ ;
+    }
+  } 
+
+  {
+    ftrigr_t a = FTRIGR_ZERO ;
+    stralloc rpsa = STRALLOC_ZERO ;
+    gid_t gid = options & 2 ? -1 : getegid() ;
+    size_t scdirlen = strlen(scdir) ;
+    unsigned int m = 0 ;
+    size_t i = 0 ;
+    uint32_t killopts = 0 ;
+    int r ;
+    uint16_t ids[ntotal] ;
+    char lname[scdirlen + maxnlen + 2] ;
+    char fn[maxlen + 5 + (sizeof(S6_SUPERVISE_EVENTDIR) > 5 ? sizeof(S6_SUPERVISE_EVENTDIR) : 5)] ;
+    if (!ftrigr_startf(&a, deadline, stamp)) return -1 ;
+    memcpy(lname, scdir, scdirlen) ;
+    lname[scdirlen] = '/' ;
+    for (; i < n ; i++)
+    {
+      char const *src = servicedirs[i] ;
+      size_t len = strlen(servicedirs[i]) ;
+      int h = bitarray_peek(locked, i) ;
+      memcpy(fn, servicedirs[i], len) ;
+      if (!h)
+      {
+        ids[m] = registerit(&a, fn, len, gid, options, deadline, stamp) ;
+        if (!ids[m++]) goto err ;
+        if (bitarray_peek(logged, i))
+        {
+          memcpy(fn + len, "/log", 4) ;
+          ids[m] = registerit(&a, fn, len + 4, gid, options, deadline, stamp) ;
+          if (!ids[m++]) goto err ;
+        }
+      }
+      fn[len] = 0 ;
+      strcpy(lname + scdirlen + 1, names[i]) ;
+      if (servicedirs[i][0] != '/')
+      {
+        rpsa.len = 0 ;
+        if (sarealpath(&rpsa, servicedirs[i]) < 0 || !stralloc_0(&rpsa)) goto err ;
+        src = rpsa.s ;
+      }
+      if (symlink(src, lname) < 0 && (!h || errno != EEXIST)) goto err ;
+    }
+    stralloc_free(&rpsa) ;
+    r = s6_svc_writectl(scdir, S6_SVSCAN_CTLDIR, "a", 1) ;
+    if (r <= 0) goto errsa ;
+    killopts = 3 ;
+    if (ftrigr_wait_and(&a, ids, m, deadline, stamp) < 0) goto errsa ;
+    ftrigr_end(&a) ;
+    return m ;
+
+   err:
+    stralloc_free(&rpsa) ;
+   errsa:
+    ftrigr_end(&a) ;
+    do_unlink(scdir, names, i, killopts | (options & 4)) ;
+  }
+  return -1 ;
+}
diff --git a/src/libs6/s6_supervise_unlink.c b/src/libs6/s6_supervise_unlink.c
index 2e5a9ec..cc263e4 100644
--- a/src/libs6/s6_supervise_unlink.c
+++ b/src/libs6/s6_supervise_unlink.c
@@ -3,7 +3,7 @@
 #include <errno.h>
 #include <string.h>
 #include <unistd.h>
-#include <limits.h>
+#include <sys/stat.h>
 
 #include <skalibs/posixplz.h>
 #include <skalibs/allreadwrite.h>
@@ -11,19 +11,13 @@
 
 #include <s6/s6-supervise.h>
 
-#ifdef PATH_MAX
-# define S6_PATH_MAX PATH_MAX
-#else
-# define S6_PATH_MAX 4096
-#endif
-
 void s6_supervise_unlink (char const *scdir, char const *name, uint32_t options)
 {
   int e = errno ;
-  int fd = -1 ;
+  int fd = -1, fdlog = -1 ;
   size_t scdirlen = strlen(scdir) ;
   size_t namelen = strlen(name) ;
-  char fn[scdirlen + namelen + sizeof(S6_SUPERVISE_CTLDIR) + 10] ;
+  char fn[scdirlen + namelen + sizeof(S6_SUPERVISE_CTLDIR) + 14] ;
   memcpy(fn, scdir, scdirlen) ;
   fn[scdirlen] = '/' ;
   memcpy(fn + scdirlen + 1, name, namelen) ;
@@ -37,7 +31,11 @@ void s6_supervise_unlink (char const *scdir, char const *name, uint32_t options)
     memcpy(fn + scdirlen + 1 + namelen, "/" S6_SUPERVISE_CTLDIR, sizeof(S6_SUPERVISE_CTLDIR)) ;
     memcpy(fn + scdirlen + 1 + namelen + sizeof(S6_SUPERVISE_CTLDIR), "/control", 9) ;
     fd = open_write(fn) ;
+    memcpy(fn + scdirlen + 1 + namelen, "/log/" S6_SUPERVISE_CTLDIR, 4 + sizeof(S6_SUPERVISE_CTLDIR)) ;
+    memcpy(fn + scdirlen + 5 + namelen + sizeof(S6_SUPERVISE_CTLDIR), "/control", 9) ;
+    fdlog = open_write(fn) ;
   }
+  
   fn[scdirlen + 1 + namelen] = 0 ;
   unlink_void(fn) ;
   if (fd >= 0)
@@ -45,5 +43,10 @@ void s6_supervise_unlink (char const *scdir, char const *name, uint32_t options)
     fd_write(fd, "xd", 1 + !!(options & 2)) ;
     fd_close(fd) ;
   }
+  if (fdlog >= 0)
+  {
+    fd_write(fdlog, "xo", 1 + !!(options & 2)) ;
+    fd_close(fdlog) ;
+  }
   errno = e ;
 }
diff --git a/src/supervision/deps-exe/s6-svdir-link b/src/supervision/deps-exe/s6-svdir-link
new file mode 100644
index 0000000..16eaae2
--- /dev/null
+++ b/src/supervision/deps-exe/s6-svdir-link
@@ -0,0 +1,5 @@
+${LIBS6}
+-lskarnet
+${SOCKET_LIB}
+${SYSCLOCK_LIB}
+${SPAWN_LIB}
diff --git a/src/supervision/deps-exe/s6-svdir-unlink b/src/supervision/deps-exe/s6-svdir-unlink
new file mode 100644
index 0000000..08815d9
--- /dev/null
+++ b/src/supervision/deps-exe/s6-svdir-unlink
@@ -0,0 +1,2 @@
+${LIBS6}
+-lskarnet
diff --git a/src/supervision/s6-svdir-link.c b/src/supervision/s6-svdir-link.c
new file mode 100644
index 0000000..6eeb0a2
--- /dev/null
+++ b/src/supervision/s6-svdir-link.c
@@ -0,0 +1,104 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <stdint.h>
+#include <string.h>
+#include <sys/stat.h>
+
+#include <skalibs/types.h>
+#include <skalibs/sgetopt.h>
+#include <skalibs/tai.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/djbunix.h>
+
+#include <s6/s6-supervise.h>
+
+#define USAGE "s6-svdir-link [ -d ] [ -f ] [ -P | -p ] [ -t timeout ] scandir name servicedir"
+#define dieusage() strerr_dieusage(100, USAGE)
+
+static inline void checkscandir (char const *s)
+{
+  int r ;
+  int fd ;
+  size_t len = strlen(s) ;
+  char fn[len + 6 + sizeof(S6_SVSCAN_CTLDIR)] ;
+  memcpy(fn, s, len) ;
+  memcpy(fn + len, "/" S6_SVSCAN_CTLDIR "/lock", 6 + sizeof(S6_SVSCAN_CTLDIR)) ;
+  fd = open_read(fn) ;
+  if (fd < 0) strerr_diefu2sys(111, "open ", fn) ;
+  r = fd_islocked(fd) ;
+  if (r < 0) strerr_diefu2sys(111, "check lock on ", fn) ;
+  if (!r) strerr_dief2x(1, "s6-svscan not running on ", s) ;
+  fd_close(fd) ;
+}
+
+static inline void checkservicedir (char const *s)
+{
+  int r ;
+  struct stat st ;
+  size_t len = strlen(s) ;
+  char fn[len + 9] ;
+  memcpy(fn, s, len) ;
+  memcpy(fn + len, "/run", 4) ;
+  if (stat(fn, &st) == -1) strerr_diefu2sys(111, "stat ", fn) ;
+  if (!(st.st_mode & S_IXUSR)) strerr_dief2x(100, fn, " is not executable") ;
+  r = s6_svc_ok(s) ;
+  if (r < 0) strerr_diefu2sys(111, "check supervision status of ", s) ;
+  if (r) strerr_warnw2x("supervisor already running on ", s) ;
+  memcpy(fn + len + 1, "log", 4) ;
+  if (stat(fn, &st) == -1)
+  {
+    if (errno != ENOENT) strerr_diefu2sys(111, "stat ", fn) ;
+  }
+  else
+  {
+    if (!S_ISDIR(st.st_mode)) strerr_dief2x(100, fn, " is not a directory") ;
+    memcpy(fn + len + 4, "/run", 5) ;
+    if (stat(fn, &st) == -1) strerr_diefu2sys(111, "stat ", fn) ;
+    if (!(st.st_mode & S_IXUSR)) strerr_dief2x(100, fn, " is not executable") ;
+    fn[len + 4] = 0 ;
+    r = s6_svc_ok(fn) ;
+    if (r < 0) strerr_diefu2sys(111, "check supervision status of ", fn) ;
+    if (r) strerr_warnw2x("supervisor already running on ", fn) ;
+  } 
+}
+
+int main (int argc, char const *const *argv)
+{
+  tain tto = TAIN_INFINITE_RELATIVE ;
+  uint32_t options = 0 ;
+  PROG = "s6-svdir-link" ;
+  {
+    unsigned int t = 0 ;
+    subgetopt l = SUBGETOPT_ZERO ;
+    for (;;)
+    {
+      int opt = subgetopt_r(argc, argv, "dfPpt:", &l) ;
+      if (opt == -1) break ;
+      switch (opt)
+      {
+        case 'd' : options |= 4 ; break ;
+        case 'f' : options |= 1 ; break ;
+        case 'P' : options |= 2 ; break ;
+        case 'p' : options &= ~2U ; break ;
+        case 't' : if (!uint0_scan(l.arg, &t)) dieusage() ; break ;
+        default : dieusage() ;
+      }
+    }
+    argc -= l.ind ; argv += l.ind ;
+    if (t) tain_from_millisecs(&tto, t) ;
+  }
+  if (argc < 3) dieusage() ;
+
+  if (!argv[0][0]) strerr_dief1x(100, "invalid scandir") ;
+  if (!argv[1][0]) strerr_dief1x(100, "invalid name") ;
+  if (!argv[2][0]) strerr_dief1x(100, "invalid servicedir") ;
+  checkscandir(argv[0]) ;
+
+  tain_now_set_stopwatch_g() ;
+  tain_add_g(&tto, &tto) ;
+
+  if (s6_supervise_link_names_g(argv[0], argv + 2, argv + 1, 1, options, &tto) == -1)
+    strerr_diefu6sys(111, "link servicedir ", argv[2], " into scandir ", argv[0], " with name ", argv[1]) ;
+  return 0 ;
+}
diff --git a/src/supervision/s6-svdir-unlink.c b/src/supervision/s6-svdir-unlink.c
new file mode 100644
index 0000000..88eedbe
--- /dev/null
+++ b/src/supervision/s6-svdir-unlink.c
@@ -0,0 +1,36 @@
+/* ISC license. */
+
+#include <stdint.h>
+
+#include <skalibs/sgetopt.h>
+#include <skalibs/strerr2.h>
+
+#include <s6/s6-supervise.h>
+
+#define USAGE "s6-svdir-unlink [ -d ] [ -x ] scandir servicename"
+#define dieusage() strerr_dieusage(100, USAGE)
+
+int main (int argc, char const *const *argv)
+{
+  uint32_t options = 0 ;
+  PROG = "s6-svdir-link" ;
+  {
+    subgetopt l = SUBGETOPT_ZERO ;
+    for (;;)
+    {
+      int opt = subgetopt_r(argc, argv, "dx", &l) ;
+      if (opt == -1) break ;
+      switch (opt)
+      {
+        case 'd' : options = 3 ; break ;
+        case 'x' : options = 1 ; break ;
+        default : dieusage() ;
+      }
+    }
+    argc -= l.ind ; argv += l.ind ;
+  }
+  if (argc < 2) dieusage() ;
+
+  s6_supervise_unlink(argv[0], argv[1], options) ;
+  return 0 ;
+}