parser (roughly 80x faster).
The absolutely latest version of Bison (1.875c) is required for
reentrant GLR support, as well as a recent version of Flex (say,
2.5.31). Note that most Unix distributions ship with the
prehistoric Flex 2.5.4, which doesn't support reentrancy.
Nix. This is to prevent Berkeley DB from becoming wedged.
Unfortunately it is not possible to throw C++ exceptions from a
signal handler. In fact, you can't do much of anything except
change variables of type `volatile sig_atomic_t'. So we set an
interrupt flag in the signal handler and check it at various
strategic locations in the code (by calling checkInterrupt()).
Since this is unlikely to cover all cases (e.g., (semi-)infinite
loops), sometimes SIGTERM may now be required to kill Nix.
the output path of a derivation, not the path of its store
expression. This ensures that changes that affect the path of the
store expression but not the output path, do not affect the
`installed' state of a derivation.
it automatically removes log files when they are no longer needed.
*** IMPORTANT ***
If you have an existing Nix installation, you must checkpoint the
Nix database to prevent recent transactions from being undone. Do
the following:
- optional: make a backup of $prefix/var/nix/db.
- run `db_checkpoint' from Berkeley DB 4.1:
$ db_checkpoint -h $prefix/var/nix/db -1
- optional (?): run `db_recover' from Berkeley DB 4.1:
$ db_recover -h $prefix/var/nix/db
- remove $prefix/var/nix/db/log* and $prefix/var/nix/db/__db*
path of the Nix expression to be used with the import, upgrade, and
query commands. For instance,
$ nix-env -I ~/nixpkgs/pkgs/system/i686-linux.nix
$ nix-env --query --available [aka -qa]
sylpheed-0.9.7
bison-1.875
pango-1.2.5
subversion-0.35.1
...
$ nix-env -i sylpheed
$ nix-env -u subversion
There can be only one default at a time.
* If the path to a Nix expression is a symlink, follow the symlink
prior to resolving relative path references in the expression.
the symlink ~/.nix-userenv to the given argument (which defaults to
.../links/current). /etc/profile.d/nix-profile creates this symlink
if it doesn't exist yet. Example use:
$ nix-env -l my_profile -i foo.nix subversion quake
$ nix-env -p my_profile
I don't like the term "profile". Let's deprecate it :-)
nix-env -u foo.nix strategoxt
to replace the installed `strategoxt' derivation with the one from `foo.nix', if
the latter has a higher version number. This is a no-op if `strategoxt' is not
installed. Wildcards are also accepted, so
nix-env -u foo.nix '*'
will replace any installed derivation with newer versions from `foo.nix', if
available.
The notion of "version number" is somewhat ad hoc, but should be useful in most
cases, as evidenced by the following unit tests for the version comparator:
TEST("1.0", "2.3", -1);
TEST("2.1", "2.3", -1);
TEST("2.3", "2.3", 0);
TEST("2.5", "2.3", 1);
TEST("3.1", "2.3", 1);
TEST("2.3.1", "2.3", 1);
TEST("2.3.1", "2.3a", 1);
TEST("2.3pre1", "2.3", -1);
TEST("2.3pre3", "2.3pre12", -1);
TEST("2.3a", "2.3c", -1);
TEST("2.3pre1", "2.3c", -1);
TEST("2.3pre1", "2.3q", -1);
(-1 = less, 0 = equal, 1 = greater)
* A new verbosity level `lvlInfo', between `lvlError' and `lvlTalkative'. This is
the default for `nix-env', so without any `-v' flags users should get useful
output, e.g.,
$ nix-env -u foo.nix strategoxt
upgrading `strategoxt-0.9.2' to `strategoxt-0.9.3'
turned out to be a huge performance bottleneck (the text to printed
would always be evaluated, even when it was above the verbosity
level). This reduces fix-ng execution time by over 50%.
gprof(1) is very useful. :-)
The ATerm library doesn't search the heap for pointers to ATerms
when garbage collecting. As a result, C++ containers such as
`map<ATerm, ATerm>' will cause pointer to be hidden from the garbage
collector, causing crashes. Instead, we now use ATermTables.
writes stdout/stderr of the builder to ${prefix}/var/log/nix/x,
where x is the file name of the derivation expression, e.g.,
/nix/var/log/nix/54256391624be04fcb426048ae3ea0a4-d-pan-0.14.2.nix
Note that consecutive builds of the same expression overwrite,
rather than append to, existing log files.
* Fixed a segfault caused by the buffering of stderr.
* Fix now allows the specification of the full output path. This
should be used with great care, since it by-passes the normal hash
generation.
* Incremented the version number to 0.4 (prerelease).
log on commit. This means that there is a small change that some
transactions may be rolled back in case of a system crash, but this
should not be a problem (it merely might cause some expression
realisations to be rolled back), and it vastly improves performance.
* Upgraded to ATerm 2.0.5 (which also includes Armijn's 64-bit
patches).
* Point $HOME to a non-existing path when building to prevent certain tools (such as
wget) from falling back on /etc/passwd to locate the home directory (which we
don't want them to look at since it's not declared as an input).
keys to reference slice elements, e.g.,
Slice(["1ef7..."], [("/nix/store/1ef7...-foo", "1ef7", ["8c99..."]), ...])
This was wrong, since ids represent contents, not locations. Therefore we
now have:
Slice(["/nix/store/1ef7..."], [("/nix/store/1ef7...-foo", "1ef7", ["/nix/store/8c99-..."]), ...])
* Fix a bug in the computation of slice closures that could cause slice
elements to be duplicated.
("srcs", [Relative("foo/bar.c"), Relative("foo/baz.h")])
The result is an environment variable that contains the path names of the
inputs separated by spaces (so this is not safe for values containing
spaces).
builder using the `args' binding:
("args", ["bla", True, IncludeFix("aterm/aterm.fix")])
Note that packages can also be declared as inputs by specifying them
in the argument list.
process is already holding a lock on a path, it may acquire the lock
again without blocking or failing). (This might be dangerous, not
sure). Necessary for fast builds to work.
normal form in a single transaction to ensure that if we crash,
either everything is registered or nothing is. This is for
recoverability: unregistered paths in the store can be deleted
arbitrarily, while registered paths can only be deleted by running
the garbage collector.
* Open all database tables (Db objects) at initialisation time, not
every time they are used. This is necessary because tables have to
outlive all transactions that refer to them.
