X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=TODO;h=cb0036a15645cb3f44737c33a9ad15eba61d4fcd;hp=5fe1a207344e3f995ef71af6c790335fd1b3d120;hb=86349ffe49092345269762e3274121133604c3d4;hpb=c221efb2de9a9d8500c0c6baf943bff0d8f87e7f diff --git a/TODO b/TODO index 5fe1a2073..cb0036a15 100644 --- a/TODO +++ b/TODO @@ -1,82 +1,207 @@ Bugfixes: -* Re-enable "fsck -l" when it is ready: - https://bugs.freedesktop.org/show_bug.cgi?id=79576#c5 * Should systemctl status \* work on all unit types, not just .service? -* enabling an instance unit creates a pointless link, and - the unit will be started with getty@getty.service: - $ systemctl enable getty@.service - ln -s '/usr/lib/systemd/system/getty@.service' '/etc/systemd/system/getty.target.wants/getty@.service' - * Dangling symlinks of .automount unit files in .wants/ directories, set up automount points even when the original .automount file did not exist anymore. Only the .mount unit was still around. * properly handle .mount unit state tracking when two mount points are stacked one on top of another on the exact same mount point. -* shorten the message to sane length: +* ExecStart with unicode characters fails in strv_split_quoted: - Cannot add dependency job for unit display-manager.service, ignoring: Unit display-manager.service failed to load: No such file or directory. See system logs and 'systemctl status display-manager.service' for details. + [Service] + Environment=ONE='one' "TWO='two two' too" THREE= + ExecStart=/bin/python3 -c 'import sys;print(sys.argv)' $ONE $TWO $THREE -* sd_bus_unref() is broken regarding self-references and "pseudo thread-safety". - See the comment in sd_bus_unref() for more.. +* MEMORY return code is overloaded for syntax errors in the command line. + str_split_quoted() should return a real return code, so spawn_child can + report the failure properly. External: -* Fedora: when installing fedora with yum --installroot /var/run is a directory, not a symlink - https://bugzilla.redhat.com/show_bug.cgi?id=975864 * Fedora: add an rpmlint check that verifies that all unit files in the RPM are listed in %systemd_post macros. * Fedora: post FPC ticket to move add %tmpfiles_create to the packaging guidelines +* Fedora: move kernel image to /usr/lib/modules/, kernel-install will take care of populating /boot + +* Fedora: remove /etc/resolv.conf tmpfiles hack + +* wiki: update journal format documentation for lz4 additions + +* When lz4 gets an API for lz4 command output, make use of it to + compress coredumps in a way compatible with /usr/bin/lz4. + Features: -* ProtectedHome= turn into enum, and add "full" option that also marks /etc read-only +* increase CORE resource limit by default for all services, so that coredumpctl becomes useful -* generator that automatically discovers btrfs subvolumes, identifies their purpose based on some xattr on them. +* firstboot: make it useful to be run immediately after yum --installroot to set up a machine. -* support setting empty environment variables with Environment= and EnvironmentFile= +* networkd-wait-online really should have a timeout by default -* tmpfiles: figure out relation between Z and m? +* expose orientation sensors through logind -* systemd-notify: fake ucred of msg to PID of parent, if that works, with fallback to our own if it doesn't. +* add infrastructure to allocate dynamic/transient users and UID ranges, for use in user-namespaced containers, per-seat gdm login screens and gdm guest sessions -* machined/machinectl: sort IP addresses we return by scope and protocol -* machined: write NSS module for looking up IP addresses for machines +* resolved: maybe randomize DNS UDP source ports -* timer units: actually add extra delays to timer units with high AccuracySec values, don't start them already when we are awake... +* resolved: maybe compare query section of DNS replies -* timesyncd: - - hookup with networkd: NTP servers from dhcp +* machined: add an API so that libvirt-lxc can inform us about network interfaces being removed or added to an existing machine -* a way for container managers to turn off getty starting via $container_headless= or so... +* maybe add support for specifier expansion in user.conf, specifically DefaultEnvironment= -* figure out a nice way how we can let the admin know what child/sibling unit causes cgroup membership for a specific unit +* kdbus: set the bus-wide creds sender requirement mask to ANY -* add a kernel command line option to enable the debug shell +* kdbus: busnames.target should get pulled in by basic.target -* journalctl: add the ability to look for the most recent process of a binary. journalctl /usr/bin/X11 --pid=-1 or so... +* code cleanup: retire FOREACH_WORD_QUOTED, port to unquote_first_word() loops instead -* set NOTIFY_SOCKET also for control processes +* logind: when the power button is pressed short, just popup a logout dialog. If it is pressed for 1s, do the usual shutdown. Inspiration are Macs here. -* drop parsing of chkconfig header lines from service.c +* optionally support running journald from the command line for testing purposes in external projects -* mount_cgroup_controllers(): symlinks need to get the label applied +* journald: allow per-priority and per-service retention times when rotating/vacuuming -* For timer units: add some mechanisms so that timer units that trigger immediately on boot do not have the services they run added to the initial transaction and thus confuse Type=idle. +* introduce systemd-timesync-wait.service or so to sync on an NTP fix? -* Add RPM macros for registering/unregistering binfmt drop-ins +* systemd --user should issue sd_notify() upon reaching basic.target, not on becoming idle -* Add timeout to early-boot, and shut down the system if it is hit. Solves the laptop-in-bag problem and is useful for embedded cases +* configure.ac pretends dbus was optional but actually hardcodes use of dbus' pkg-config file to determine various dbus dirs such as policy and activation dirs -* Run most system services with cgroupfs read-only and procfs with a more secure mode +* consider showing the unit names during boot up in the status output, not just the unit descriptions -* sd-event: generate a failure of a default event loop is executed out-of-thread +* dhcp: do we allow configuring dhcp routes on interfaces that are not the one we got the dhcp info from? + +* maybe allow timer units with an empty Units= setting, so that they + can be used for resuming the system but nothing else. + +* what to do about udev db binary stability for apps? (raw access is not an option) + +* maybe provide an API to allow migration of foreign PIDs into existing scopes. + +* PID 1 doesn't apply nspawns devices cgroup policy + +* maybe support a new very "soft" reboot mode, that simply kills all processes, disassembles everything, flushes /run and sysvipc, and then reexecs systemd again + +* man: document that corrupted journal files is nothing to act on + +* bus-proxy: when passing messages from kdbus, make sure we properly + handle the case where a large number of fds is appended that we + cannot pass into sendmsg() of the AF_UNIX sokcet (which only accepts + 253 messages) + +* man: maybe use the word "inspect" rather than "introspect"? + +* introduce machines.target to order after all nspawn instances + +* systemd-nspawn@.service should fail if some nspawn arg is invalid, with Type=notify + +* "machinectl list" should probably show columns for OS version and IP addresses + +* systemctl: if it fails, show log output? + +* maybe add "systemctl edit" that copies unit files from /usr/lib/systemd/system to /etc/systemd/system and invokes vim on them + +* refcounting in sd-resolve is borked + +* exponential backoff in timesyncd and resolved when we cannot reach a server + +* journald: make use of uid-range.h to managed uid ranges to split + journals in. + +* tmpfiles: port to unquote_many_words(), similar to sysusers + +* unquote_many_words() should probably be used by a lot of code that + currently uses FOREACH_WORD and friends. For example, most conf + parsing callbacks should use it. + +* logind: make the Suspend()/Hibernate() bus calls wait for the for + the job to be completed. before returning, so that clients can wait + for "systemctl suspend" to finish to know when the suspending is + complete. + +* merge ~/.local/share and ~/.local/lib into one similar /usr/lib and /usr/share.... + +* journald: allows specification of UID range for splitting up journal files + +* systemd.show_status= should probably have a mode where only failed + units are shown. + +* networkd: + - add LLDP client side support + - the DHCP lease data (such as NTP/DNS) is still made available when + a carrier is lost on a link. It should be removed instantly. + - .network setting that allows overriding of the hostname to send to the dhcp server + http://lists.freedesktop.org/archives/systemd-devel/2014-July/021550.html + - expose in the API the following bits: + - option 15, domain name and/or option 119, search list + - option 12, host name and/or option 81, fqdn + - option 100, 101, timezone + - option 123, 144, geolocation + - option 252, configure http proxy (PAC/wpad) + - networkd's dhcp server should transparently pass on the DNS and + NTP server list it got from user configuration and its dhcp client + to clients. It should also pass on its own timezone information. + - provide a way to define a per-network interface default metric value + for all routes to it. possibly a second default for DHCP routes. + - allow Name= to be specified repeatedly in the [Match] section. Maybe also + support Name=foo*|bar*|baz ? + +* resolved: + - put networkd events and rtnl events at a higher priority, so that + we always process them before we process client requests + - DNSSEC + - use base64 for key presentation? + - add display of private key types (http://tools.ietf.org/html/rfc4034#appendix-A.1.1)? + - add nice formatting of DNS timestamps + - DNS + - search paths + - mDNS/DNS-SD + - avahi compat + - DNS-SD service registration from socket units + - edns0 + - dname + - cname on PTR (?) + +* Ignore .busname units on classic D-Bus boots, systemd-resolved cannot be started on kdbus + without the active policy and should get a Wants=org.freedesktop.resolve1.busname to + pull-in the policy. + +* Allow multiple ExecStart= for all Type= settings, so that we can cover rescue.service nicely + +* Add a new verb "systemctl top" + +* logind: allow users to kill or lock their own sessions + +* add new gpt type for btrfs volumes + +* support empty /etc boots nicely: + - nspawn/gpt-generator: introduce new gpt partition type for /usr + - fstab-generator: support systemd.volatile=yes|no|state on the kernel cmdline, too, similar to nspawn's --volatile= + +* generator that automatically discovers btrfs subvolumes, identifies their purpose based on some xattr on them. + +* support setting empty environment variables with Environment= and EnvironmentFile= + +* timer units: actually add extra delays to timer units with high AccuracySec values, don't start them already when we are awake... + +* a way for container managers to turn off getty starting via $container_headless= or so... + +* figure out a nice way how we can let the admin know what child/sibling unit causes cgroup membership for a specific unit -* add "M" as recursive version of "m" to tmpfiles, then use it for - chowning /run/log/journal (but not /var/log/journal), so that we - adjust the perms of journal files created before tmpfiles ran. +* journalctl: add the ability to look for the most recent process of a binary. journalctl /usr/bin/X11 --pid=-1 or so... + +* mount_cgroup_controllers(): symlinks need to get the label applied + +* For timer units: add some mechanisms so that timer units that trigger immediately on boot do not have the services + they run added to the initial transaction and thus confuse Type=idle. + +* Run most system services with cgroupfs read-only and procfs with a more secure mode (doesn't work, since the hidepid= option is per-pid-namespace, not per-mount) + +* sd-event: generate a failure of a default event loop is executed out-of-thread * expose "Locked" property on logind sesison objects @@ -96,10 +221,6 @@ Features: do not have to open it to know that it is not interesting for us, for the most common operations. -* support transient mount units - -* add an "input" group to udev logic and add all input devices to it - * add generator that pulls in systemd-network from containers when CAP_NET_ADMIN is set, more than the loopback device is defined, even when it is otherwise off @@ -157,10 +278,6 @@ Features: * unify dispatch table in systemctl_main() and friends -* Automatically configure swap partition to use for hibernation by looking for largest swap partition on the root disk? - -* socket-proxyd: Use sd-resolve to resolve the server address - * rfkill,backlight: we probably should run the load tools inside of the udev rules so that the state is properly initialized by the time other software sees it * After coming back from hibernation reset hibernation swap partition using the /dev/snapshot ioctl APIs @@ -187,31 +304,30 @@ Features: ReadOnlyDirectories=... for whitelisting files for a service. * sd-bus: - - make AddMatch calls on dbus1 transports async + - kdbus: maybe add euid, egid, fsuid, fsgid, controlling tty and ppid metadata fields + - see if we can introduce a new sd_bus_get_owner_machine_id() call to retrieve the machine ID of the machine of the bus itself - when kdbus does not take our message without memfds, try again with memfds - systemd-bus-proxyd needs to enforce good old XML policy - - port exit-on-idle logic to byebye ioctl - allow updating attach flags during runtime - pid1: peek into activating message when activating a service - introduce sd_bus_emit_object_added()/sd_bus_emit_object_removed() that automatically includes the build-in interfaces in the list - - constructors for bus messages should probably not be OK with a NULL bus pointer - - .busname units should not use get_user_creds()/get_cgroup_creds() but instead do NSS only in temporarily forked off child + - port to sd-resolve for connecting to TCP dbus servers - see if we can drop more message validation on the sending side - add API to clone sd_bus_message objects + - make AddMatch calls on dbus1 transports async? - kdbus: matches against source or destination pids for an "strace -p"-like feel. Problem: The PID info needs to be available in userspace too... - longer term: priority inheritance - dbus spec updates: - kdbus mapping - NameLost/NameAcquired obsolete - GVariant - - "const" properties (posted) - path escaping - update systemd.special(7) to mention that dbus.socket is only about the compatibility socket now - test bloom filter generation indexes - - port to sd-resolve for connecting to TCP dbus servers * sd-event - allow multiple signal handlers per signal? + - document chaining of signal handler for SIGCHLD and child handlers * in the final killing spree, detect processes from the root directory, and complain loudly if they have argv[0][0] == '@' set. @@ -228,22 +344,12 @@ Features: * maybe add a generator that looks for "systemd.run=" on the kernel cmdline for container usercases... -* timedatctl, localectl: possibly make some commands work without the daemon, for chroot situations... - -* timedatectl: print a nicer message when enabling ntp fails because ntpd/chrony are not installed - * cgtop: make cgtop useful in a container * test/: - add 'set -e' to scripts in test/ - make stuff in test/ work with separate output dir -* systemctl delete x.snapshot leaves no trace in logs (at least at default level). - -* make the coredump collector tool move itself into the user's cgroup - so that the coredump is properly written to the user's own journal - file. - * seems that when we follow symlinks to units we prefer the symlink destination path over /etc and /usr. We should not do that. Instead /etc should always override /run+/usr and also any symlink @@ -279,10 +385,6 @@ Features: * think about window-manager-run-as-user-service problem: exit 0 → activate shutdown.target; exit != 0 → restart service -* use "log level" rather than "log priority" everywhere - -* timedate: have global on/off switches for auto-time (NTP), and auto-timezone that connman can subscribe to. - * merge unit_kill_common() and unit_kill_context() * introduce ExecCondition= in services @@ -322,6 +424,7 @@ Features: * service: watchdog logic: for testing purposes allow ping, but do not require pong * journal: + - consider introducing implicit _TTY= + _PPID= + _EUID= + _EGID= + _FSUID= + _FSGID= fields - import and delete pstore filesystem content at startup - journald: also get thread ID from client, plus thread name - journal: when waiting for journal additions in the client always sleep at least 1s or so, in order to minimize wakeups @@ -343,17 +446,14 @@ Features: - journal-send.c, log.c: when the log socket is clogged, and we drop, count this and write a message about this when it gets unclogged again. - journal: find a way to allow dropping history early, based on priority, other rules - journal: When used on NFS, check payload hashes - - journald: check whether it is OK if the client can still modify delivered journal entries - journal live copy, based on libneon (client) and libmicrohttpd (server) - journald: add kernel cmdline option to disable ratelimiting for debug purposes - refuse taking lower-case variable names in sd_journal_send() and friends. - journald: we currently rotate only after MaxUse+MaxFilesize has been reached. - journal: deal nicely with byte-by-byte copied files, especially regards header - - journal: store euid in journal if it differs from uid - journal: sanely deal with entries which are larger than the individual file size, but where the components would fit - Replace utmp, wtmp, btmp, and lastlog completely with journal - journalctl: instead --after-cursor= maybe have a --cursor=XYZ+1 syntax? - - tmpfiles: when applying ownership to /run/log/journal, also do this for the journal fails contained in it - when a kernel driver logs in a tight loop, we should ratelimit that too. - journald: optionally, log debug messages to /run but everything else to /var - journald: when we drop syslog messages because the syslog socket is @@ -389,7 +489,6 @@ Features: about it. Should fix both to print nice actionable messages. - print nice message from systemctl --failed if there are no entries shown, and hook that into ExecStartPre of rescue.service/emergency.service - add new command to systemctl: "systemctl system-reexec" which reexecs as many daemons as virtually possible - - systemctl enable: improve the success messages (i.e. more human readable, less shell-like) - systemctl enable: fail if target to alias into does not exist? maybe show how many units are enabled afterwards? - systemctl: "Journal has been rotated since unit was started." message is misleading - support "systemctl stop foobar@.service" to stop all units matching a certain template @@ -400,13 +499,7 @@ Features: * unit install: - "systemctl mask" should find all names by which a unit is accessible (i.e. by scanning for symlinks to it) and link them all to /dev/null - - "systemctl disable" of a unit instance removes all symlinks, but should - only remove the instance symlink (systemctl disable of a template - unit however should remove them all). - systemctl list-unit-files should list generated files (and probably with a new state "generated" for them, or so) - - systemctl: maybe add "systemctl add-wants" or so... - -* deal with sendmail/postfix exclusivity * timer units: - timer units should get the ability to trigger when: @@ -417,22 +510,6 @@ Features: - when parsing calendar timestamps support the UTC timezone (even if we will not support arbitrary timezone specs, support UTC itself certainly makes sense), also support syntaxes such as +0200 - Modulate timer frequency based on battery state -* update the kernel's TZ (sys_tz) when DST changes - -* sync down the system time to the RTC when: - - CLOCK_REALTIME makes jumps (the user explicitely requested a time set) - - DST/timezone changes && ntp is active && RTC-in-localtime (never do it without ntp) - This takes care of syncing ntpdate updates to the RTC, and DST updates for localtime - mode, it will never touch the RTC if the no reliable time source is active or the - user did not request anything like it. - -* libunwind support for coredump pattern hook, and includes this in - the message for coredumps. After all, libunwind is now capable to - unwind coredumps since a few weeks ago. This probably requires that - we have nice support for multi-line messages on display in - logs-show.c. Alternatively: use libelfutil, which seems to be the - better supported alternative. - * add libsystemd-password or so to query passwords during boot using the password agent logic * If we show an error about a unit (such as not showing up) and it has no Description string, then show a description string generated form the reverse of unit_name_mangle(). @@ -441,19 +518,10 @@ Features: * fedup: do not delete initrd on switch-root * fedup: generator -* timedated: refuse time changes when NTP is on - * clean up date formatting and parsing so that all absolute/relative timestamps we format can also be parsed * on shutdown: move utmp, wall, audit logic all into PID 1 (or logind?), get rid of systemd-update-utmp-runlevel -* add "factory" instructions to setup an empty /etc + /var - - used to setup a new container from a shared /usr - - superset of tmpfiles model - - instructions shipped by packages and stored in /usr/lib/ - - compose /etc/passwd and /etc/group, copy files - - able to create uid + gid used by packages, for file ownership - * make repeated alt-ctrl-del presses printing a dump, or even force a reboot without waiting for the timeout @@ -462,9 +530,7 @@ Features: * currently x-systemd.timeout is lost in the initrd, since crypttab is copied into dracut, but fstab is not * nspawn: - - nspawn: --read-only is not applied recursively to submounts - bind mount read-only the cgroup tree higher than nspawn - - nspawn: make it work for dwalsh and shared /usr containers -- tmpfs mounts as command line parameters - refuses to boot containers without /etc/machine-id (OK?), and with empty /etc/machine-id (not OK). - support taking a btrfs snapshot at startup and dropping it afterwards @@ -481,25 +547,14 @@ Features: * make timer units go away after they elapsed -* http://lists.freedesktop.org/archives/systemd-devel/2012-September/006502.html - (network and remote-fs on shutdown) - -* come up with a nice way to write queue/read_ahead_kb for a block device without interfering with readahead - * move PID 1 segfaults to /var/lib/systemd/coredump? * create /sbin/init symlinks from the build system -* Query Paul Moore about relabelling socket fds while they are open - * allow writing multiple conditions in unit files on one line -* explore multiple service instances per listening socket idea - * MountFlags=shared acts as MountFlags=slave right now. -* ReadOnlyDirectories= is not applied recursively to submounts - * drop PID 1 reloading, only do reexecing (difficult: Reload() currently is properly synchronous, Reexec() is weird, because we cannot delay the response properly until we are back, so instead of @@ -509,10 +564,6 @@ Features: * properly handle loop back mounts via fstab, especially regards to fsck/passno -* allow services with no ExecStart= but with an ExecStop= - -* dracut-shutdown needs to be ordered before unmounting /boot - * initialize the hostname from the fs label of /, if /etc/hostname does not exist? * rename "userspace" to "core-os" @@ -540,7 +591,6 @@ Features: * ExecOnFailure=/usr/bin/foo * udev: - - remove src/udev/udev-builtin-firmware.c (CONFIG_FW_LOADER_USER_HELPER=n) - move to LGPL - kill scsi_id - add trigger --subsystem-match=usb/usb_device device @@ -568,7 +618,6 @@ Features: * when a bus name of a service disappears from the bus make sure to queue further activation requests * tmpfiles: - - check systemd-tmpfiles for selinux context hookup for mknod(), symlink() and similar - apply "x" on "D" too (see patch from William Douglas) * for services: do not set $HOME in services unless requested @@ -587,30 +636,17 @@ Features: * make sure systemd-ask-password-wall does not shutdown systemd-ask-password-console too early -* support sd_notify() style notification when reload begins (RELOADING=1), reload is finished (READY=1), and add ReloadSignal= then to use in combination - -* support sd_notify() style notification when shutting down, to make auto-exit bus services work (STOPPING=1) +* add ReloadSignal= for configuring a reload signal to use * verify that the AF_UNIX sockets of a service in the fs still exist when we start a service in order to avoid confusion when a user assumes starting a service is enough to make it accessible -* support User= and Group= attributes for AF_UNIX sockets. (difficult, requires NSS from PID 1?) - * Make it possible to set the keymap independently from the font on the kernel cmdline. Right now setting one resets also the other. * and a dbus call to generate target from current state -* readahead: - - drop /.readahead on bigger upgrades with yum - - move readahead files into /var (look for them with .path units?) - - readahead: use BTRFS_IOC_DEFRAG_RANGE instead of BTRFS_IOC_DEFRAG ioctl, with START_IO - - readahead: when bumping /sys readahead variable save mtime and compare later to detect changes - - readahead: make use of EXT4_IOC_MOVE_EXT, as used by http://e4rat.sourceforge.net/ - -* add support for /bin/mount -s - * GC unreferenced jobs (such as .device jobs) * write blog stories about: @@ -636,8 +672,6 @@ Features: * allow port=0 in .socket units -* support systemd.mask= on the kernel command line. - * recreate systemd's D-Bus private socket file on SIGUSR2 * Support --test based on current system state @@ -650,8 +684,6 @@ Features: * fingerprint.target, wireless.target, gps.target, netdevice.target -* drop cap bounding set in readahead and other services - * systemd-python: - figure out a simple way to wait for journal events in a way that works with ^C @@ -676,17 +708,13 @@ Features: * networkd: - add more keys to [Route] and [Address] sections - add support for more DHCPv4 options (and, longer term, other kinds of dynamic config) - - send hostname to DHCP server - add proper initrd support (in particular generate .network/.link files based on /proc/cmdline) - add reduced [Link] support to .network files - add Scope= parsing option for [Network] - properly handle routerless dhcp leases - - set lifetime on the address acquired from dhcp - - patch kernel to support module alias for tunnel device (ipip/sit/gre), - then remove remove libkmod dependency and CAP_SYS_MODULE - - add veth netdev support (c.f. http://shorewall.net/bridge-Shorewall-perl.html#veth) - - add tun/tap netdev support - add more attribute support for SIT tunnel + - work with non-ethernet devices + - add support for more bond options * networkd-wait-online: - make operstates to wait for configurable? @@ -694,7 +722,22 @@ Features: * dhcp: - figure out how much we can increase Maximum Message Size - export timezone information - - FORCERENEW + - support RFC4702 (pass FQDN) + +* dhcp6: + - add functions to set previously stored IPv6 addresses on startup and get + them at shutdown; store them in client->ia_na + - write more test cases + - implement and do duplicate address detection, see rfc 4862, 5.4. + - implement reconfigure support, see 5.3., 15.11. and 22.20. + - implement information request, see 1.2. and 18.1.5. + - implement support for temporary adressess (IA_TA) + - implement dhcpv6 authentication + - investigate the usefulness of Confirm messages; i.e. are there any + situations where the link changes without any loss in carrier detection + or interface down + - some servers don't do rapid commit without a filled in IA_NA, verify + this behavior External: @@ -730,6 +773,11 @@ External: * register catalog database signature as file magic +* zsh shell completion: + - - should complete options, but currently does not + - systemctl add-wants,add-requires + + Regularly: * look for close() vs. close_nointr() vs. close_nointr_nofail()