Commit graph

269 commits

Author SHA1 Message Date
Eelco Dolstra 43579c9799 Use pager for more commands 2014-08-20 21:44:55 +02:00
Eelco Dolstra 11849a320e Use proper quotes everywhere 2014-08-20 18:03:48 +02:00
Eelco Dolstra 392430b2c4 nix-store -l: Automatically pipe output into $PAGER 2014-08-20 15:12:58 +02:00
Eelco Dolstra 47e185847e Refactor option handling 2014-08-13 03:50:44 +02:00
Eelco Dolstra 1a44f1cb65 nix-copy-closure: Drop --bzip2, --xz, --show-progress
These are too difficult to implement via nix-store --serve.

‘--show-progress’ could be re-implemented fairly easily via a
sink/source wrapper class.
2014-07-24 17:11:54 +02:00
Eelco Dolstra 03103c0a36 Implement nix-copy-closure --from via nix-store --serve 2014-07-24 16:19:41 +02:00
Eelco Dolstra 62309a2c56 build-remote.pl: Be less verbose on failing builds 2014-07-24 12:43:59 +02:00
Eelco Dolstra d7a92ed4a9 nix-store --serve: Only monitor stdin during builds
Other operations cannot hang indefinitely (except when we're reading
from stdin, in which case we'll notice a client disconnect). But
monitoring works badly during compressed imports, since there the
client can close the connection before we've sent an ack.

http://hydra.nixos.org/build/12711638
2014-07-24 11:59:35 +02:00
Eelco Dolstra bd91453bb1 Pass -pthread only for programs that need it 2014-07-23 19:48:18 +02:00
Eelco Dolstra 78224cd871 nix-store --serve: Monitor for client disconnects
This is necessary because build-remote.pl now builds via ‘nix-store
--serve’. So if a build hangs without writing to stdout/stderr, and
the client disconnects, then we need to detect that.
2014-07-23 19:26:34 +02:00
Eelco Dolstra fa13d3f4f3 build-remote.pl: Fix building multiple output derivations
We were importing paths without sorting them topologically, leading to
"path is not valid" errors.

See e.g. http://hydra.nixos.org/build/12451761
2014-07-14 12:19:27 +02:00
Eelco Dolstra a5c6347ff0 build-remote.pl: Use ‘nix-store --serve’ on the remote side
This makes things more efficient (we don't need to use an SSH master
connection, and we only start a single remote process) and gets rid of
locking issues (the remote nix-store process will keep inputs and
outputs locked as long as they're needed).

It also makes it more or less secure to connect directly to the root
account on the build machine, using a forced command
(e.g. ‘command="nix-store --serve --write"’). This bypasses the Nix
daemon and is therefore more efficient.

Also, don't call nix-store to import the output paths.
2014-07-11 16:22:24 +02:00
Eelco Dolstra 7bb632b024 nix-copy-closure -s: Do substitutions via ‘nix-store --serve’
This means we no longer need an SSH master connection, since we only
execute a single command on the remote host.
2014-07-10 20:43:04 +02:00
Eelco Dolstra 8e9140cfde Refactoring: Move all fork handling into a higher-order function
C++11 lambdas ftw.
2014-07-10 16:58:09 +02:00
Eelco Dolstra 1114c7bd57 nix-copy-closure: Restore compression and the progress viewer 2014-07-10 14:15:12 +02:00
Eelco Dolstra 04170d06bf nix-copy-closure: Fix race condition
There is a long-standing race condition when copying a closure to a
remote machine, particularly affecting build-remote.pl: the client
first asks the remote machine which paths it already has, then copies
over the missing paths. If the garbage collector kicks in on the
remote machine between the first and second step, the already-present
paths may be deleted. The missing paths may then refer to deleted
paths, causing nix-copy-closure to fail. The client now performs both
steps using a single remote Nix call (using ‘nix-store --serve’),
locking all paths in the closure while querying.

I changed the --serve protocol a bit (getting rid of QueryCommand), so
this breaks the SSH substituter from older versions. But it was marked
experimental anyway.

Fixes #141.
2014-07-10 11:58:59 +02:00
Eelco Dolstra 2c3a8f787b Fix security hole in ‘nix-store --serve’
Since it didn't check that the path received from the client is a
store path, the client could dump any path in the file system.
2014-07-10 11:46:01 +02:00
Eelco Dolstra 9f9080e2c0 nix-store -l: Fetch build logs from the Internet
If a build log is not available locally, then ‘nix-store -l’ will now
try to download it from the servers listed in the ‘log-servers’ option
in nix.conf. For instance, if you have:

  log-servers = http://hydra.nixos.org/log

then it will try to get logs from http://hydra.nixos.org/log/<base
name of the store path>. So you can do things like:

  $ nix-store -l $(which xterm)

and get a log even if xterm wasn't built locally.
2014-05-21 17:19:36 +02:00
Eelco Dolstra 84813af5b9 nix-store --optimise: Remove bogus statistics 2014-05-15 11:33:46 +02:00
Eelco Dolstra 6b9cd59a41 nix-store -r: Respect --add-root for non-derivations
Fixes #68.
Fixes #117.
2014-02-26 16:32:46 +01:00
Eelco Dolstra 1aa19b24b2 Add a flag ‘--check’ to verify build determinism
The flag ‘--check’ to ‘nix-store -r’ or ‘nix-build’ will cause Nix to
redo the build of a derivation whose output paths are already valid.
If the new output differs from the original output, an error is
printed.  This makes it easier to test if a build is deterministic.
(Obviously this cannot catch all sources of non-determinism, but it
catches the most common one, namely the current time.)

For example:

  $ nix-build '<nixpkgs>' -A patchelf
  ...
  $ nix-build '<nixpkgs>' -A patchelf --check
  error: derivation `/nix/store/1ipvxsdnbhl1rw6siz6x92s7sc8nwkkb-patchelf-0.6' may not be deterministic: hash mismatch in output `/nix/store/4pc1dmw5xkwmc6q3gdc9i5nbjl4dkjpp-patchelf-0.6.drv'

The --check build fails if not all outputs are valid.  Thus the first
call to nix-build is necessary to ensure that all outputs are valid.

The current outputs are left untouched: the new outputs are either put
in a chroot or diverted to a different location in the store using
hash rewriting.
2014-02-18 01:01:14 +01:00
Eelco Dolstra 1da6ae4f99 nix-store --gc --max-freed: Support a unit specifier
E.g. "--max-freed 10G" means "free ten gigabytes".
2014-02-17 14:48:50 +01:00
Eelco Dolstra a9d99ab55f download-via-ssh: Use readStorePath 2014-02-14 12:31:10 +01:00
Eelco Dolstra dba33d4018 Minor style fixes 2014-02-14 11:48:42 +01:00
Shea Levy f67f52751f Indendation fix
Signed-off-by: Shea Levy <shea@shealevy.com>
2014-02-12 07:33:07 -05:00
Shea Levy 7438f0bc2b error messages start in lowercase
Signed-off-by: Shea Levy <shea@shealevy.com>
2014-02-12 07:26:35 -05:00
Shea Levy c89d6b9b63 nix-store --serve: Use a versioned protocol
Signed-off-by: Shea Levy <shea@shealevy.com>
2014-02-10 07:43:13 -05:00
Shea Levy 38c3beac1a Move StoreApi::serve into opServe
Signed-off-by: Shea Levy <shea@shealevy.com>
2014-02-10 06:52:48 -05:00
Shea Levy 73874629ef nix-store --serve: Use dump instead of export
Also remove signing support

Signed-off-by: Shea Levy <shea@shealevy.com>
2014-02-08 00:13:33 -05:00
Shea Levy 3a38d0f356 Add the nix-store --serve command
This is essentially the substituter API operating on the local store,
which will be used by the ssh substituter. It runs in a loop rather than
just taking one command so that in the future nix will be able to keep
one connection open for multiple instances of the substituter.

Signed-off-by: Shea Levy <shea@shealevy.com>
2014-02-08 00:13:32 -05:00
Eelco Dolstra 0c6d62cf27 Remove Automakefiles 2014-02-01 13:54:38 +01:00
Eelco Dolstra 16e7d69209 Update Makefile variable names 2014-02-01 13:54:38 +01:00
Eelco Dolstra e0234dfddc Rename Makefile -> local.mk 2014-01-30 12:11:06 +01:00
Eelco Dolstra 81628a6ccc Merge branch 'master' into make
Conflicts:
	src/libexpr/eval.cc
2014-01-21 15:30:01 +01:00
Eelco Dolstra b4c684e0f9 Update Makefiles 2014-01-09 16:53:47 +01:00
Eelco Dolstra 8931bf7168 Doh 2013-12-20 13:09:12 +00:00
Eelco Dolstra 65a6452240 nix-shell: Handle --option correctly
Fixes #181.
2013-12-20 13:10:14 +01:00
Eelco Dolstra 7ce0e05ad8 Rename Makefile.new -> Makefile 2013-11-25 15:25:13 +00:00
Eelco Dolstra 6dd74b48f8 Support building dynamic libraries 2013-11-22 20:56:58 +00:00
Eelco Dolstra 754c05ed6c Rename $(here) to $(d) for brevity, and remove trailing slash 2013-11-22 16:45:52 +00:00
Eelco Dolstra b8e9efc476 New non-recursive, plain Make-based build system 2013-11-22 15:54:18 +01:00
Eelco Dolstra b09b87321c nix-store --export: Export paths in topologically sorted order
Fixes #118.
2013-05-23 14:55:36 -04:00
Eelco Dolstra bdd4646338 Revert "Prevent config.h from being clobbered"
This reverts commit 28bba8c44f.
2013-03-08 01:24:59 +01:00
Eelco Dolstra 28bba8c44f Prevent config.h from being clobbered 2013-03-07 23:55:55 +01:00
Eelco Dolstra 5526a282b5 Security: Don't allow builders to change permissions on files they don't own
It turns out that in multi-user Nix, a builder may be able to do

  ln /etc/shadow $out/foo

Afterwards, canonicalisePathMetaData() will be applied to $out/foo,
causing /etc/shadow's mode to be set to 444 (readable by everybody but
writable by nobody).  That's obviously Very Bad.

Fortunately, this fails in NixOS's default configuration because
/nix/store is a bind mount, so "ln" will fail with "Invalid
cross-device link".  It also fails if hard-link restrictions are
enabled, so a workaround is:

  echo 1 > /proc/sys/fs/protected_hardlinks

The solution is to check that all files in $out are owned by the build
user.  This means that innocuous operations like "ln
${pkgs.foo}/some-file $out/" are now rejected, but that already failed
in chroot builds anyway.
2013-02-26 02:30:19 +01:00
Eelco Dolstra d6143801fd Support the colonies 2013-01-30 18:50:58 +01:00
Eelco Dolstra 99ed558a93 Correctly handle missing logs 2013-01-22 22:07:25 +01:00
Eelco Dolstra 536c85ea49 Store build logs in /nix/var/log/nix/drvs/<XX>
...where <XX> is the first two characters of the derivation.
Otherwise /nix/var/log/nix/drvs may become so large that we run into
all sorts of weird filesystem limits/inefficiences.  For instance,
ext3/ext4 filesystems will barf with "ext4_dx_add_entry:1551:
Directory index full!" once you hit a few million files.
2013-01-17 15:47:26 +01:00
Eelco Dolstra 2754a07ead nix-store -q --roots: Respect the gc-keep-outputs/gc-keep-derivations settings
So if a path is not garbage solely because it's reachable from a root
due to the gc-keep-outputs or gc-keep-derivations settings, ‘nix-store
-q --roots’ now shows that root.
2012-12-20 18:41:44 +01:00
Eelco Dolstra 46a369ad95 Make "nix-build -A <derivation>.<output>" do the right thing
For example, given a derivation with outputs "out", "man" and "bin":

  $ nix-build -A pkg

produces ./result pointing to the "out" output;

  $ nix-build -A pkg.man

produces ./result-man pointing to the "man" output;

  $ nix-build -A pkg.all

produces ./result, ./result-man and ./result-bin;

  $ nix-build -A pkg.all -A pkg2

produces ./result, ./result-man, ./result-bin and ./result-2.
2012-11-26 15:39:10 +01:00
Eelco Dolstra 9de6bc5d05 nix-store -r: Add ‘--ignore-unknown’ flag
This flag causes paths that do not have a known substitute to be
quietly ignored.  This is mostly useful for Charon, allowing it to
speed up deployment by letting a machine use substitutes for all
substitutable paths, instead of uploading them.  The latter is
frequently faster, e.g. if the target machine has a fast Internet
connection while the source machine is on a slow ADSL line.
2012-11-20 00:27:25 +01:00
Eelco Dolstra bf3725da2a nix-store -r: Don't quietly ignore missing paths 2012-11-19 23:51:56 +01:00
Eelco Dolstra a562d544d8 When ‘--help’ is given, just run ‘man’ to show the manual page
I.e. do what git does.  I'm too lazy to keep the builtin help text up
to date :-)

Also add ‘--help’ to various commands that lacked it
(e.g. nix-collect-garbage).
2012-10-03 16:40:09 -04:00
Eelco Dolstra 2001895f3d Add a --repair flag to ‘nix-store -r’ to repair derivation outputs
With this flag, if any valid derivation output is missing or corrupt,
it will be recreated by using a substitute if available, or by
rebuilding the derivation.  The latter may use hash rewriting if
chroots are not available.
2012-10-02 17:13:46 -04:00
Eelco Dolstra cf46f19444 nix-store -r: Get rid of an unnecessary call to buildPaths/ensurePaths 2012-10-02 16:00:09 -04:00
Eelco Dolstra 8e3a7bd712 nix-store --verify: Add an option ‘--repair’ to repair all missing/corrupt paths
Also, return a non-zero exit code if errors remain after
verifying/repairing.
2012-10-02 15:12:56 -04:00
Eelco Dolstra 9958bd6992 Add operation ‘nix-store --repair-path’
This operation allows fixing corrupted or accidentally deleted store
paths by redownloading them using substituters, if available.

Since the corrupted path cannot be replaced atomically, there is a
very small time window (one system call) during which neither the old
(corrupted) nor the new (repaired) contents are available.  So
repairing should be used with some care on critical packages like
Glibc.
2012-10-02 14:08:59 -04:00
Eelco Dolstra e94806d030 Merge branch 'master' into no-manifests 2012-08-27 11:09:07 -04:00
Eelco Dolstra a9e6752bbd Include the output name in the GC root link
Output names are now appended to resulting GC symlinks, e.g. by
nix-build.  For backwards compatibility, if the output is named "out",
nothing is appended.  E.g. doing "nix-build -A foo" on a derivation
that produces outputs "out", "bin" and "dev" will produce symlinks
"./result", "./result-bin" and "./result-dev", respectively.
2012-08-24 16:58:11 -04:00
Eelco Dolstra 01d56c1eec Drop the block count in the garbage collector 2012-08-01 22:34:46 -04:00
Eelco Dolstra 967d066d8e nix-store --gc: Make ‘--max-freed 0’ do the right thing
That is, delete almost nothing (it will still remove unused links from
/nix/store/.links).
2012-08-01 19:14:58 -04:00
Eelco Dolstra 97421eb5ec Refactor settings processing
Put all Nix configuration flags in a Settings object.
2012-07-30 19:55:41 -04:00
Eelco Dolstra 8c79100839 Merge branch 'master' into no-manifests 2012-07-26 15:14:33 -04:00
Eelco Dolstra 564fb7d9fa optimiseStore(): Use a content-addressed file store in /nix/store/.links
optimiseStore() now creates persistent, content-addressed hard links
in /nix/store/.links.  For instance, if it encounters a file P with
hash H, it will create a hard link

  P' = /nix/store/.link/<H>

to P if P' doesn't already exist; if P' exist, then P is replaced by a
hard link to P'.  This is better than the previous in-memory map,
because it had the tendency to unnecessarily replace hard links with a
hard link to whatever happened to be the first file with a given hash
it encountered.  It also allows on-the-fly, incremental optimisation.
2012-07-23 17:14:15 -04:00
Eelco Dolstra b7fd2c2822 Use "#pragma once" to prevent repeated header file inclusion 2012-07-18 14:59:03 -04:00
Eelco Dolstra 667d5f1936 Rename queryValidPaths() to queryAllValidPaths() 2012-07-11 10:49:04 -04:00
Eelco Dolstra 1aba0bf0fa nix-store -r: do substitutions in parallel
I.e. when multiple non-derivation arguments are passed to ‘nix-store
-r’ to be substituted, do them in parallel.
2012-06-27 16:58:15 -04:00
Eelco Dolstra 881beb170d "nix-store -l": support compressed logs 2012-05-30 00:00:02 -04:00
Eelco Dolstra 4bc4da331a Reserve some disk space for the garbage collector
We can't open a SQLite database if the disk is full.  Since this
prevents the garbage collector from running when it's most needed, we
reserve some dummy space that we can free just before doing a garbage
collection.  This actually revives some old code from the Berkeley DB
days.

Fixes #27.
2012-05-29 22:59:12 -04:00
Eelco Dolstra 34ea91b259 Include --keep-going in --help 2012-04-04 16:22:32 +02:00
Eelco Dolstra 8be1979f1a Remove the --max-links GC option
We don't need this anymore now that current filesystems support more
than 32,000 files in a directory.
2012-03-26 20:00:02 +02:00
Eelco Dolstra d5a5a83ad4 Use data() instead of c_str() where appropriate 2012-02-09 18:27:45 +01:00
Eelco Dolstra 4e624849b6 * Added a command ‘nix-store --print-env $drvpath’ that prints out the
environment of the given derivation in a format that can be sourced
  by the shell, e.g.

  $ eval "$(nix-store --print-env $(nix-instantiate /etc/nixos/nixpkgs -A pkg))"
  $ NIX_BUILD_TOP=/tmp
  $ source $stdenv/setup

  This is especially useful to reproduce the environment used to build
  a package outside of its builder for development purposes.

  TODO: add a nix-build option to do the above and fetch the
  dependencies of the derivation as well.
2012-01-17 23:07:22 +00:00
Eelco Dolstra 93b56acb2d * Support multiple outputs in nix-store (specifically the ‘--query’
and ‘--realise’ actions).
2011-12-30 17:25:19 +00:00
Eelco Dolstra 273b288a7e * importPath() -> importPaths(). Because of buffering of the input
stream it's now necessary for the daemon to process the entire
  sequence of exported paths, rather than letting the client do it.
2011-12-16 22:31:25 +00:00
Eelco Dolstra 49f59dceca * Move parseHash16or32 into libutil, and use in nix-hash. 2011-12-02 11:47:06 +00:00
Eelco Dolstra 5bbd693cae * Add an API function exportPaths() that provides the functionality of
‘nix-store --export’.
* Add a Perl module that provides the functionality of
  ‘nix-copy-closure --to’.  This is used by build-remote.pl so it no
  longer needs to start a separate nix-copy-closure process.  Also, it
  uses the Perl API to do the export, so it doesn't need to start a
  separate nix-store process either.  As a result, nix-copy-closure
  and build-remote.pl should no longer fail on very large closures due
  to an "Argument list too long" error.  (Note that having very many
  dependencies in a single derivation can still fail because the
  environment can become too large.  Can't be helped though.)
2011-11-23 15:13:37 +00:00
Eelco Dolstra e6cb3d0a0d * Added a command ‘nix-store --verify-paths PATHS’ to check whether
the contents of any of the given store paths have been modified.
  E.g.

    $ nix-store --verify-path $(nix-store -qR /var/run/current-system)
    path `/nix/store/m2smyiwbxidlprfxfz4rjlvz2c3mg58y-etc' was modified! expected hash `fc87e271c5fdf179b47939b08ad13440493805584b35e3014109d04d8436e7b8', got `20f1a47281b3c0cbe299ce47ad5ca7340b20ab34246426915fce0ee9116483aa'

  All paths are checked; the exit code is 1 if any path has been
  modified, 0 otherwise.
2011-09-06 12:06:30 +00:00
Eelco Dolstra 93227ff65c * Eliminate all uses of the global variable ‘store’ from libstore.
This should also fix:

    nix-instantiate: ./../boost/shared_ptr.hpp:254: T* boost::shared_ptr<T>::operator->() const [with T = nix::StoreAPI]: Assertion `px != 0' failed.

  which was caused by hashDerivationModulo() calling the ‘store’
  object (during store upgrades) before openStore() assigned it.
2011-08-31 21:11:50 +00:00
Eelco Dolstra e60c962fb8 * Add an operation `nix-store -q --size'. 2010-11-17 12:40:52 +00:00
Eelco Dolstra a3883cbd28 * Store the size of a store path in the database (to be precise, the
size of the NAR serialisation of the path, i.e., `nix-store --dump
  PATH').  This is useful for Hydra.
2010-11-16 17:11:46 +00:00
Eelco Dolstra fb9368b5a0 * Sync with the trunk. 2010-11-16 12:49:47 +00:00
Eelco Dolstra 705868a8a9 * Make sure that config.h is included before the system headers,
because it defines _FILE_OFFSET_BITS.  Without this, on 
  OpenSolaris the system headers define it to be 32, and then 
  the 32-bit stat() ends up being called with a 64-bit "struct 
  stat", or vice versa.

  This also ensures that we get 64-bit file sizes everywhere.

* Remove the redundant call to stat() in parseExprFromFile().
  The file cannot be a symlink because that's the exit condition
  of the loop before.
2010-10-04 17:55:38 +00:00
Eelco Dolstra bf87cc44b4 * Sync with the trunk. 2010-06-21 07:55:38 +00:00
Ludovic Courtès 8bcdd36f10 Add XML output to `nix-store'.
* src/nix-store/Makefile.am (nix_store_SOURCES): Add `xmlgraph.cc' and
  `xmlgraph.hh'.

* src/nix-store/help.txt (Operations): Document `--xml'.

* src/nix-store/nix-store.cc (opQuery): Handle `--xml'.

* src/nix-store/xmlgraph.cc, src/nix-store/xmlgraph.hh: New files.
2010-05-31 16:36:24 +00:00
Ludovic Courtès da52f8bea0 Comment out dead code in `nix-store'.
* src/nix-store/dotgraph.cc (pathLabel): Move within #if 0 section.
2010-05-31 16:36:20 +00:00
Eelco Dolstra f92c9a0ac5 * Allow unprivileged users to do `nix-store --clear-failed-paths' and
`nix-store --query-failed-paths'.
2010-05-04 10:45:10 +00:00
Eelco Dolstra ef337f7089 2010-04-26 12:58:12 +00:00
Eelco Dolstra 6199f9b93e * Added a command `nix-store --clear-failed-paths <PATHS>' to clear
the "failed" status of the given store paths.  The special value `*'
  clears all failed paths.
2010-04-26 12:56:42 +00:00
Eelco Dolstra 2398af13c5 * Add an command `nix-store --query-failed-paths' to list the cached
failed paths (when using the `build-cache-failure' option).
2010-04-26 12:43:42 +00:00
Eelco Dolstra f3b8833a48 * Drop the dependency on the ATerm library. 2010-04-19 14:51:58 +00:00
Eelco Dolstra 594eaddd11 * When using the included sqlite/aterm libraries, build with
--enable-shared.
* In libutil/libstore/libexpr etc., link against sqlite and aterm.
* Some more header file hygiene.
2010-03-02 15:58:13 +00:00
Eelco Dolstra fefd467539 * `helpText' is now zero-terminated. 2010-02-24 13:24:27 +00:00
Eelco Dolstra fae0427324 * ADDITIONAL_NETWORK_LIBS -> LIBS. 2010-02-24 12:25:48 +00:00
Eelco Dolstra fa6a4fcb11 * Add ${sqlite_lib} everywhere. Just adding it in `libstore' doesn't
work on x86_64 when sqlite is compiled statically.
2010-02-24 12:18:48 +00:00
Eelco Dolstra fdcaf37361 * Made `nix-store -qR --include-outputs' much faster if there are
multiple paths specified on the command line (from O(n * m) to O(n +
  m), where n is the number of arguments and m is the size of the
  closure).
2010-01-25 17:18:44 +00:00
Eelco Dolstra 9b8fda796b * Templatise getIntArg / string2Int. 2009-11-24 12:26:25 +00:00
Eelco Dolstra 3d55f1eb57 * A command `nix-store --query --roots <paths>' to find the garbage
collector roots that point (directly or indirectly) to the given
  paths.
2009-11-23 18:16:25 +00:00
Eelco Dolstra ae6bf87273 * `nix-store --gc --print-roots': also print the path of the actual
root symlink, not just its target.  E.g.:

  /nix/var/nix/profiles/system-99-link -> /nix/store/76kwf88657nq7wgk1hx3l1z5q91zb9wd-system
2009-11-23 17:23:12 +00:00
Eelco Dolstra 8824d60fe5 * Remove the --use-atime / --max-atime garbage collector flags. Many
(Linux) machines no longer maintain the atime because it's too
  expensive, and on the machines where --use-atime is useful (like the
  buildfarm), reading the atimes on the entire Nix store takes way too
  much time to make it practical.
2009-11-20 17:12:38 +00:00