Commit Graph

187 Commits

Author SHA1 Message Date
Peter Eisentraut 4d6a854f17 Put new command-line options into alphabetical order 2018-06-04 15:03:15 -04:00
Tom Lane 1368e92e16 Support --no-comments in pg_dump, pg_dumpall, pg_restore.
We have switches already to suppress other subsidiary object properties,
such as ACLs, security labels, ownership, and tablespaces, so just on
the grounds of symmetry we should allow suppressing comments as well.
Also, commit 0d4e6ed30 added a positive reason to have this feature,
i.e. to allow obtaining the old behavior of selective pg_restore should
anyone desire that.

Recent commits have removed the cases where pg_dump emitted comments on
built-in objects that the restoring user might not have privileges to
comment on, so the original primary motivation for this feature is gone,
but it still seems at least somewhat useful in its own right.

Robins Tharakan, reviewed by Fabrízio Mello

Discussion: https://postgr.es/m/CAEP4nAx22Z4ch74oJGzr5RyyjcyUSbpiFLyeYXX8pehfou92ug@mail.gmail.com
2018-01-25 15:27:24 -05:00
Tom Lane b3f8401205 Move handling of database properties from pg_dumpall into pg_dump.
This patch rearranges the division of labor between pg_dump and pg_dumpall
so that pg_dump itself handles all properties attached to a single
database.  Notably, a database's ACL (GRANT/REVOKE status) and local GUC
settings established by ALTER DATABASE SET and ALTER ROLE IN DATABASE SET
can be dumped and restored by pg_dump.  This is a long-requested
improvement.

"pg_dumpall -g" will now produce only role- and tablespace-related output,
nothing about individual databases.  The total output of a regular
pg_dumpall run remains the same.

pg_dump (or pg_restore) will restore database-level properties only when
creating the target database with --create.  This applies not only to
ACLs and GUCs but to the other database properties it already handled,
that is database comments and security labels.  This is more consistent
and useful, but does represent an incompatibility in the behavior seen
without --create.

(This change makes the proposed patch to have pg_dump use "COMMENT ON
DATABASE CURRENT_DATABASE" unnecessary, since there is no case where
the command is issued that we won't know the true name of the database.
We might still want that patch as a feature in its own right, but pg_dump
no longer needs it.)

pg_dumpall with --clean will now drop and recreate the "postgres" and
"template1" databases in the target cluster, allowing their locale and
encoding settings to be changed if necessary, and providing a cleaner
way to set nondefault tablespaces for them than we had before.  This
means that such a script must now always be started in the "postgres"
database; the order of drops and reconnects will not work otherwise.
Without --clean, the script will not adjust any database-level properties
of those two databases (including their comments, ACLs, and security
labels, which it formerly would try to set).

Another minor incompatibility is that the CREATE DATABASE commands in a
pg_dumpall script will now always specify locale and encoding settings.
Formerly those would be omitted if they matched the cluster's default.
While that behavior had some usefulness in some migration scenarios,
it also posed a significant hazard of unwanted locale/encoding changes.
To migrate to another locale/encoding, it's now necessary to use pg_dump
without --create to restore into a database with the desired settings.

Commit 4bd371f6f's hack to emit "SET default_transaction_read_only = off"
is gone: we now dodge that problem by the expedient of not issuing ALTER
DATABASE SET commands until after reconnecting to the target database.
Therefore, such settings won't apply during the restore session.

In passing, improve some shaky grammar in the docs, and add a note pointing
out that pg_dumpall's output can't be expected to load without any errors.
(Someday we might want to fix that, but this is not that patch.)

Haribabu Kommi, reviewed at various times by Andreas Karlsson,
Vaishnavi Prabakaran, and Robert Haas; further hacking by me.

Discussion: https://postgr.es/m/CAJrrPGcUurV0eWTeXODwsOYFN=Ekq36t1s0YnFYUNzsmRfdAyA@mail.gmail.com
2018-01-22 14:09:09 -05:00
Peter Eisentraut 3c49c6facb Convert documentation to DocBook XML
Since some preparation work had already been done, the only source
changes left were changing empty-element tags like <xref linkend="foo">
to <xref linkend="foo"/>, and changing the DOCTYPE.

The source files are still named *.sgml, but they are actually XML files
now.  Renaming could be considered later.

In the build system, the intermediate step to convert from SGML to XML
is removed.  Everything is build straight from the source files again.
The OpenSP (or the old SP) package is no longer needed.

The documentation toolchain instructions are updated and are much
simpler now.

Peter Eisentraut, Alexander Lakhin, Jürgen Purtz
2017-11-23 09:44:28 -05:00
Peter Eisentraut 1ff01b3902 Convert SGML IDs to lower case
IDs in SGML are case insensitive, and we have accumulated a mix of upper
and lower case IDs, including different variants of the same ID.  In
XML, these will be case sensitive, so we need to fix up those
differences.  Going to all lower case seems most straightforward, and
the current build process already makes all anchors and lower case
anyway during the SGML->XML conversion, so this doesn't create any
difference in the output right now.  A future XML-only build process
would, however, maintain any mixed case ID spellings in the output, so
that is another reason to clean this up beforehand.

Author: Alexander Lakhin <exclusion@gmail.com>
2017-10-20 19:26:10 -04:00
Peter Eisentraut c29c578908 Don't use SGML empty tags
For DocBook XML compatibility, don't use SGML empty tags (</>) anymore,
replace by the full tag name.  Add a warning option to catch future
occurrences.

Alexander Lakhin, Jürgen Purtz
2017-10-17 15:10:33 -04:00
Peter Eisentraut cf851519d4 pg_dump: Support using synchronized snapshots on standbys
This became possible by commit
6c2003f8a1.  This just makes pg_dump aware
of it and updates the documentation.

Author: Petr Jelinek <petr.jelinek@2ndquadrant.com>
2017-08-16 19:46:50 -04:00
Robert Haas 23d7680d04 pg_dump: Add a --load-via-partition-root option.
Rushabh Lathia, reviewed and somewhat revised by me.  Testing by
Rajkumar Raghuwanshi.

Discussion: http://postgr.es/m/CAGPqQf0C1he087bz9xRBOGZBuESYz9X=Fp8Ca_g+TfHgAff75g@mail.gmail.com
2017-08-14 22:54:41 -04:00
Peter Eisentraut 0d9bdbcaae Put documentation of options and commands in more alphabetical order 2017-06-14 11:10:17 -04:00
Peter Eisentraut 96e1cb4c0f pg_dump: Add --no-publications option
Author: Michael Paquier <michael.paquier@gmail.com>
2017-05-12 09:15:40 -04:00
Peter Eisentraut 26aa1cf376 pg_dump: Add --no-subscriptions option
Author: Michael Paquier <michael.paquier@gmail.com>
Reviewed-by: Petr Jelinek <petr.jelinek@2ndquadrant.com>
2017-05-09 10:58:06 -04:00
Peter Eisentraut a9254e675b pg_dump: Always dump subscriptions NOCONNECT
This removes the pg_dump option --no-subscription-connect and makes it
the default.  Dumping a subscription so that it activates right away
when restored is not very useful, because the state of the publication
server is unclear.

Discussion: https://www.postgresql.org/message-id/e4fbfad5-c6ac-fd50-6777-18c84b34eb2f@2ndquadrant.com
2017-04-13 12:01:27 -04:00
Peter Eisentraut c31671f9b5 pg_dump: Dump subscriptions by default
Dump subscriptions if the current user is a superuser, otherwise write a
warning and skip them.  Remove the pg_dump option
--include-subscriptions.

Discussion: https://www.postgresql.org/message-id/e4fbfad5-c6ac-fd50-6777-18c84b34eb2f@2ndquadrant.com
2017-04-13 12:01:27 -04:00
Peter Eisentraut 7c4f52409a Logical replication support for initial data copy
Add functionality for a new subscription to copy the initial data in the
tables and then sync with the ongoing apply process.

For the copying, add a new internal COPY option to have the COPY source
data provided by a callback function.  The initial data copy works on
the subscriber by receiving COPY data from the publisher and then
providing it locally into a COPY that writes to the destination table.

A WAL receiver can now execute full SQL commands.  This is used here to
obtain information about tables and publications.

Several new options were added to CREATE and ALTER SUBSCRIPTION to
control whether and when initial table syncing happens.

Change pg_dump option --no-create-subscription-slots to
--no-subscription-connect and use the new CREATE SUBSCRIPTION
... NOCONNECT option for that.

Author: Petr Jelinek <petr.jelinek@2ndquadrant.com>
Tested-by: Erik Rijkers <er@xs4all.nl>
2017-03-23 08:55:37 -04:00
Andrew Dunstan 96a7128b7b Sync pg_dump and pg_dumpall output
Before exiting any files are fsync'ed. A --no-sync option is also
provided for a faster exit if desired.

Michael Paquier.

Reviewed by Albe Laurenz

Discussion: https://postgr.es/m/CAB7nPqS1uZ=Ov+UruW6jr3vB-S_DLVMPc0dQpV-fTDjmm0ZQMg@mail.gmail.com
2017-03-22 10:20:13 -04:00
Peter Eisentraut 665d1fad99 Logical replication
- Add PUBLICATION catalogs and DDL
- Add SUBSCRIPTION catalog and DDL
- Define logical replication protocol and output plugin
- Add logical replication workers

From: Petr Jelinek <petr@2ndquadrant.com>
Reviewed-by: Steve Singer <steve@ssinger.info>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Erik Rijkers <er@xs4all.nl>
Reviewed-by: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
2017-01-20 09:04:49 -05:00
Joe Conway 0a85c10225 Improve RLS documentation with respect to COPY
Documentation for pg_restore said COPY TO does not support row security
when in fact it should say COPY FROM. Fix that.

While at it, make it clear that "COPY FROM" does not allow RLS to be
enabled and INSERT should be used instead. Also that SELECT policies
will apply to COPY TO statements.

Back-patch to 9.5 where RLS first appeared.

Author: Joe Conway
Reviewed-By: Dean Rasheed and Robert Haas
Discussion: https://postgr.es/m/5744FA24.3030008%40joeconway.com
2016-12-22 17:56:50 -08:00
Stephen Frost 4fafa579b0 Add --no-blobs option to pg_dump
Add an option to exclude blobs when running pg_dump.  By default, blobs
are included but this option can be used to exclude them while keeping
the rest of the dump.

Commment updates and regression tests from me.

Author: Guillaume Lelarge
Reviewed-by: Amul Sul
Discussion: https://postgr.es/m/VisenaEmail.48.49926ea6f91dceb6.15355a48249@tc7-visena
2016-11-29 11:09:35 -05:00
Stephen Frost b57c8333b5 Clarify pg_dump -b documentation
The documentation around the -b/--blobs option to pg_dump seemed to
imply that it might be possible to add blobs to a "schema-only" dump or
similar.  Clarify that blobs are data and therefore will only be
included in dumps where data is being included, even when -b is used to
request blobs be included.

The -b option has been around since before 9.2, so back-patch to all
supported branches.

Discussion: https://postgr.es/m/20161119173316.GA13284@tamriel.snowman.net
2016-11-29 10:35:04 -05:00
Tom Lane 64f3524e2c Remove pg_dump/pg_dumpall support for dumping from pre-8.0 servers.
The need for dumping from such ancient servers has decreased to about nil
in the field, so let's remove all the code that catered to it.  Aside
from removing a lot of boilerplate variant queries, this allows us to not
have to cope with servers that don't have (a) schemas or (b) pg_depend.
That means we can get rid of assorted squishy code around that.  There
may be some nonobvious additional simplifications possible, but this patch
already removes about 1500 lines of code.

I did not remove the ability for pg_restore to read custom-format archives
generated by these old versions (and light testing says that that does
still work).  If you have an old server, you probably also have a pg_dump
that will work with it; but you have an old custom-format backup file,
that might be all you have.

It'd be possible at this point to remove fmtQualifiedId()'s version
argument, but I refrained since that would affect code outside pg_dump.

Discussion: <2661.1475849167@sss.pgh.pa.us>
2016-10-12 12:20:02 -04:00
Peter Eisentraut 9b7bb106e0 doc: Fix option order in man pages and fix typos 2016-07-06 21:09:26 -04:00
Tom Lane 50e5315a58 Further improve documentation about --quote-all-identifiers switch.
Mention it in the Notes section too, per suggestion from David Johnston.

Discussion: <20160520165824.22598.31426@wrigleys.postgresql.org>
2016-05-20 15:51:57 -04:00
Tom Lane 960be4a998 Improve documentation about pg_dump's --quote-all-identifiers switch.
Per bug #14152 from Alejandro Martínez.  Back-patch to all supported
branches.

Discussion: <20160520165824.22598.31426@wrigleys.postgresql.org>
2016-05-20 14:59:47 -04:00
Tom Lane 00cdd83521 Adopt the GNU convention for handling tar-archive members exceeding 8GB.
The POSIX standard for tar headers requires archive member sizes to be
printed in octal with at most 11 digits, limiting the representable file
size to 8GB.  However, GNU tar and apparently most other modern tars
support a convention in which oversized values can be stored in base-256,
allowing any practical file to be a tar member.  Adopt this convention
to remove two limitations:
* pg_dump with -Ft output format failed if the contents of any one table
exceeded 8GB.
* pg_basebackup failed if the data directory contained any file exceeding
8GB.  (This would be a fatal problem for installations configured with a
table segment size of 8GB or more, and it has also been seen to fail when
large core dump files exist in the data directory.)

File sizes under 8GB are still printed in octal, so that no compatibility
issues are created except in cases that would have failed entirely before.

In addition, this patch fixes several bugs in the same area:

* In 9.3 and later, we'd defined tarCreateHeader's file-size argument as
size_t, which meant that on 32-bit machines it would write a corrupt tar
header for file sizes between 4GB and 8GB, even though no error was raised.
This broke both "pg_dump -Ft" and pg_basebackup for such cases.

* pg_restore from a tar archive would fail on tables of size between 4GB
and 8GB, on machines where either "size_t" or "unsigned long" is 32 bits.
This happened even with an archive file not affected by the previous bug.

* pg_basebackup would fail if there were files of size between 4GB and 8GB,
even on 64-bit machines.

* In 9.3 and later, "pg_basebackup -Ft" failed entirely, for any file size,
on 64-bit big-endian machines.

In view of these potential data-loss bugs, back-patch to all supported
branches, even though removal of the documented 8GB limit might otherwise
be considered a new feature rather than a bug fix.
2015-11-21 20:21:31 -05:00
Peter Eisentraut 213335c145 Order some new options on man pages more sensibly, minor improvements 2015-09-17 20:57:47 -04:00
Teodor Sigaev d02426029b Check existency of table/schema for -t/-n option (pg_dump/pg_restore)
Patch provides command line option --strict-names which requires that at
least one table/schema should present for each -t/-n option.

Pavel Stehule <pavel.stehule@gmail.com>
2015-09-14 16:19:49 +03:00
Peter Eisentraut 103ef20211 doc: Spell checking 2015-09-10 21:35:06 -04:00
Tom Lane 5671aaca87 Improve pg_restore's -t switch to match all types of relations.
-t will now match views, foreign tables, materialized views, and sequences,
not only plain tables.  This is more useful, and also more consistent with
the behavior of pg_dump's -t switch, which has always matched all relation
types.

We're still not there on matching pg_dump's behavior entirely, so mention
that in the docs.

Craig Ringer, reviewed by Pavel Stehule
2015-07-02 18:13:34 -04:00
Peter Eisentraut a85054181b doc: Add note to pg_dump man page about pg_dumpall
suggested by Joshua Drake
2015-06-13 21:45:56 -04:00
Fujii Masao 232cd63b1f Remove -i/--ignore-version option from pg_dump, pg_dumpall and pg_restore.
The commit c22ed3d523 turned
the -i/--ignore-version options into no-ops and marked as deprecated.
Considering we shipped that in 8.4, it's time to remove all trace of
those switches, per discussion. We'd still have to wait a couple releases
before it'd be safe to use -i for something else, but it'd be a start.
2015-06-04 19:54:43 +09:00
Simon Riggs be1cc8f46f Add pg_dump --snapshot option
Allows pg_dump to use a snapshot previously defined by a concurrent
session that has either used pg_export_snapshot() or obtained a
snapshot when creating a logical slot. When this option is used with
parallel pg_dump, the snapshot defined by this option is used and no
new snapshot is taken.

Simon Riggs and Michael Paquier
2014-11-17 22:15:07 +00:00
Stephen Frost 6550b901fe Code review for row security.
Buildfarm member tick identified an issue where the policies in the
relcache for a relation were were being replaced underneath a running
query, leading to segfaults while processing the policies to be added
to a query.  Similar to how TupleDesc RuleLocks are handled, add in a
equalRSDesc() function to check if the policies have actually changed
and, if not, swap back the rsdesc field (using the original instead of
the temporairly built one; the whole structure is swapped and then
specific fields swapped back).  This now passes a CLOBBER_CACHE_ALWAYS
for me and should resolve the buildfarm error.

In addition to addressing this, add a new chapter in Data Definition
under Privileges which explains row security and provides examples of
its usage, change \d to always list policies (even if row security is
disabled- but note that it is disabled, or enabled with no policies),
rework check_role_for_policy (it really didn't need the entire policy,
but it did need to be using has_privs_of_role()), and change the field
in pg_class to relrowsecurity from relhasrowsecurity, based on
Heikki's suggestion.  Also from Heikki, only issue SET ROW_SECURITY in
pg_restore when talking to a 9.5+ server, list Bypass RLS in \du, and
document --enable-row-security options for pg_dump and pg_restore.

Lastly, fix a number of minor whitespace and typo issues from Heikki,
Dimitri, add a missing #include, per Peter E, fix a few minor
variable-assigned-but-not-used and resource leak issues from Coverity
and add tab completion for role attribute bypassrls as well.
2014-09-24 16:32:22 -04:00
Peter Eisentraut 9a218c02b8 doc: Put new options in right order on reference pages 2014-07-15 15:08:16 -04:00
Alvaro Herrera 9067310cc5 pg_dump et al: Add --if-exists option
This option makes pg_dump, pg_dumpall and pg_restore inject an IF EXISTS
clause to each DROP command they emit.  (In pg_dumpall, the clause is
not added to individual objects drops, but rather to the CREATE DATABASE
commands, as well as CREATE ROLE and CREATE TABLESPACE.)

This allows for a better user dump experience when using --clean in case
some objects do not already exist.  Per bug #7873 by Dave Rolsky.

Author: Pavel Stěhule
Reviewed-by: Jeevan Chalke, Álvaro Herrera, Josh Kupershmidt
2014-03-03 15:02:18 -03:00
Peter Eisentraut bb4eefe7bf doc: Improve DocBook XML validity
DocBook XML is superficially compatible with DocBook SGML but has a
slightly stricter DTD that we have been violating in a few cases.
Although XSLT doesn't care whether the document is valid, the style
sheets don't necessarily process invalid documents correctly, so we need
to work toward fixing this.

This first commit moves the indexterms in refentry elements to an
allowed position.  It has no impact on the output.
2014-02-23 21:31:08 -05:00
Peter Eisentraut cdeb79adcf Fix typos 2013-09-15 11:01:14 -04:00
Bruce Momjian 605b4c5a6b pg_dump docs: use escaped double-quotes, for Windows
On Unix, you can embed double-quotes in single-quotes, and via versa.
However, on Windows, you can only escape double-quotes in double-quotes,
so use that in the pg_dump -t/table example.
Backpatch to 9.3.
Report from Mike Toews
2013-07-01 14:52:59 -04:00
Peter Eisentraut 8b5a3998a1 Remove whitespace from end of lines 2013-05-30 21:05:07 -04:00
Peter Eisentraut 256f6ba78a Documentation spell checking and markup improvements 2013-05-20 21:13:13 -04:00
Peter Eisentraut a9bb274f90 doc: Fix some whitespace issues in the man pages 2013-05-13 21:59:39 -04:00
Andrew Dunstan 9e257a181c Add parallel pg_dump option.
New infrastructure is added which creates a set number of workers
(threads on Windows, forked processes on Unix). Jobs are then
handed out to these workers by the master process as needed.
pg_restore is adjusted to use this new infrastructure in place of the
old setup which created a new worker for each step on the fly. Parallel
dumps acquire a snapshot clone in order to stay consistent, if
available.

The parallel option is selected by the -j / --jobs command line
parameter of pg_dump.

Joachim Wieland, lightly editorialized by Andrew Dunstan.
2013-03-24 11:27:20 -04:00
Heikki Linnakangas 691e595dd9 Add -d/--dbname option to pg_dump.
You could already pass a database name just by passing it as the last
option, without -d. This is an alias for that, like the -d/--dbname option
in psql and many other client applications. For consistency.
2013-02-25 19:39:04 +02:00
Magnus Hagander be926474be Make pg_dump exclude unlogged table data on hot standby slaves
Noted by Joe Van Dyk
2013-01-25 09:46:07 +01:00
Peter Eisentraut 42218f29af doc: "only relevant" -> "relevant only"
Karl O. Pinc
2012-11-11 22:50:24 -05:00
Tom Lane 5a39114fe7 In pg_dump, dump SEQUENCE SET items in the data not pre-data section.
Represent a sequence's current value as a separate TableDataInfo dumpable
object, so that it can be dumped within the data section of the archive
rather than in pre-data.  This fixes an undesirable inconsistency between
the meanings of "--data-only" and "--section=data", and also fixes dumping
of sequences that are marked as extension configuration tables, as per a
report from Marko Kreen back in July.  The main cost is that we do one more
SQL query per sequence, but that's probably not very meaningful in most
databases.

Back-patch to 9.1, since it has the extension configuration issue even
though not the --section switch.
2012-10-26 12:12:42 -04:00
Tom Lane edef20f6e1 Fix pg_dump's handling of DROP DATABASE commands in --clean mode.
In commit 4317e0246c, I accidentally broke
this behavior while rearranging code to ensure that --create wouldn't
affect whether a DATABASE entry gets put into archive-format output.
Thus, 9.2 would issue a DROP DATABASE command in --clean mode, which is
either useless or dangerous depending on the usage scenario.
It should not do that, and no longer does.

A bright spot is that this refactoring makes it easy to allow the
combination of --clean and --create to work sensibly, ie, emit DROP
DATABASE then CREATE DATABASE before reconnecting.  Ordinarily we'd
consider that a feature addition and not back-patch it, but it seems
silly to not include the extra couple of lines required in the 9.2
version of the code.

Per report from Guillaume Lelarge, though this is slightly more extensive
than his proposed patch.
2012-10-20 16:58:32 -04:00
Tom Lane 4317e0246c Rewrite --section option to decouple it from --schema-only/--data-only.
The initial implementation of pg_dump's --section option supposed that the
existing --schema-only and --data-only options could be made equivalent to
--section settings.  This is wrong, though, due to dubious but long since
set-in-stone decisions about where to dump SEQUENCE SET items, as seen in
bug report from Martin Pitt.  (And I'm not totally convinced there weren't
other bugs, either.)  Undo that coupling and instead drive --section
filtering off current-section state tracked as we scan through the TOC
list to call _tocEntryRequired().

To make sure those decisions don't shift around and hopefully save a few
cycles, run _tocEntryRequired() only once per TOC entry and save the result
in a new TOC field.  This required minor rejiggering of ACL handling but
also allows a far cleaner implementation of inhibit_data_for_failed_table.

Also, to ensure that pg_dump and pg_restore have the same behavior with
respect to the --section switches, add _tocEntryRequired() filtering to
WriteToc() and WriteDataChunks(), rather than trying to implement section
filtering in an entirely orthogonal way in dumpDumpableObject().  This
required adjusting the handling of the special ENCODING and STDSTRINGS
items, but they were pretty weird before anyway.

Minor other code review for the patch, too.
2012-05-29 23:22:14 -04:00
Peter Eisentraut fe2534e534 Some reference page improvements
initdb: Add -T option
oid2name: Put options in some non-random order
pg_dump: Put --section option in the right place

And some additional markup and terminology improvements.
2012-05-20 01:15:55 +03:00
Peter Eisentraut c8e086795a Remove whitespace from end of lines
pgindent and perltidy should clean up the rest.
2012-05-15 22:19:41 +03:00
Peter Eisentraut 1715ff1128 doc: Fix for too many brackets in command synopses on man pages
The default for the choice attribute of the <arg> element is "opt",
which would normally put the argument inside brackets.  But the DSSSL
stylesheets contain a hack that treats <arg> directly inside <group>
specially, so that <group><arg>-x</arg><arg>-y</arg></group> comes out
as [ -x | -y ] rather than [ [-x] | [-y] ], which it would technically
be.  But when building man pages, this doesn't work, and so the
command synopses on the man pages contain lots of extra brackets.

By putting choice="opt" or choice="plain" explicitly on every <arg>
and <group> element, we avoid any toolchain dependencies like that,
and it also makes it clearer in the source code what is meant.

In passing, make some small corrections in the documentation about
which arguments are really optional or not.
2012-05-03 22:58:00 +03:00