config.pm

开源备份软件源码 AMANDA, the Advanced Maryland Automatic Network Disk Archiver, is a backup system that a

# This file was automatically generated by SWIG (http://www.swig.org).
# Version 1.3.31
#
# Don't modify this file, modify the SWIG interface instead.

package Amanda::Config;
require Exporter;
require DynaLoader;
@ISA = qw(Exporter DynaLoader);
package Amanda::Configc;
bootstrap Amanda::Config;
package Amanda::Config;
@EXPORT = qw( );

# ---------- BASE METHODS -------------

package Amanda::Config;

sub TIEHASH {
    my ($classname,$obj) = @_;
    return bless $obj, $classname;
}

sub CLEAR { }

sub FIRSTKEY { }

sub NEXTKEY { }

sub FETCH {
    my ($self,$field) = @_;
    my $member_func = "swig_${field}_get";
    $self->$member_func();
}

sub STORE {
    my ($self,$field,$newval) = @_;
    my $member_func = "swig_${field}_set";
    $self->$member_func($newval);
}

sub this {
    my $ptr = shift;
    return tied(%$ptr);
}


# ------- FUNCTION WRAPPERS --------

package Amanda::Config;

*getconf = *Amanda::Configc::getconf;
*getconf_seen = *Amanda::Configc::getconf_seen;
*getconf_byname = *Amanda::Configc::getconf_byname;
*getconf_list = *Amanda::Configc::getconf_list;
*lookup_tapetype = *Amanda::Configc::lookup_tapetype;
*tapetype_getconf = *Amanda::Configc::tapetype_getconf;
*tapetype_name = *Amanda::Configc::tapetype_name;
*tapetype_seen = *Amanda::Configc::tapetype_seen;
*lookup_dumptype = *Amanda::Configc::lookup_dumptype;
*dumptype_getconf = *Amanda::Configc::dumptype_getconf;
*dumptype_name = *Amanda::Configc::dumptype_name;
*dumptype_seen = *Amanda::Configc::dumptype_seen;
*lookup_interface = *Amanda::Configc::lookup_interface;
*interface_getconf = *Amanda::Configc::interface_getconf;
*interface_name = *Amanda::Configc::interface_name;
*interface_seen = *Amanda::Configc::interface_seen;
*lookup_holdingdisk = *Amanda::Configc::lookup_holdingdisk;
*getconf_holdingdisks = *Amanda::Configc::getconf_holdingdisks;
*holdingdisk_next = *Amanda::Configc::holdingdisk_next;
*holdingdisk_getconf = *Amanda::Configc::holdingdisk_getconf;
*holdingdisk_name = *Amanda::Configc::holdingdisk_name;
*holdingdisk_seen = *Amanda::Configc::holdingdisk_seen;
*getconf_unit_divisor = *Amanda::Configc::getconf_unit_divisor;
*new_config_overwrites = *Amanda::Configc::new_config_overwrites;
*free_config_overwrites = *Amanda::Configc::free_config_overwrites;
*add_config_overwrite = *Amanda::Configc::add_config_overwrite;
*add_config_overwrite_opt = *Amanda::Configc::add_config_overwrite_opt;
*apply_config_overwrites = *Amanda::Configc::apply_config_overwrites;
*config_init = *Amanda::Configc::config_init;
*config_uninit = *Amanda::Configc::config_uninit;
*get_config_options = *Amanda::Configc::get_config_options;
*get_config_name = *Amanda::Configc::get_config_name;
*get_config_dir = *Amanda::Configc::get_config_dir;
*get_config_filename = *Amanda::Configc::get_config_filename;
*dump_configuration = *Amanda::Configc::dump_configuration;
*config_dir_relative = *Amanda::Configc::config_dir_relative;
*taperalgo2str = *Amanda::Configc::taperalgo2str;
*find_multiplier = *Amanda::Configc::find_multiplier;

# ------- VARIABLE STUBS --------

package Amanda::Config;

*CNF_ORG = *Amanda::Configc::CNF_ORG;
*CNF_CONF = *Amanda::Configc::CNF_CONF;
*CNF_INDEX_SERVER = *Amanda::Configc::CNF_INDEX_SERVER;
*CNF_TAPE_SERVER = *Amanda::Configc::CNF_TAPE_SERVER;
*CNF_AUTH = *Amanda::Configc::CNF_AUTH;
*CNF_SSH_KEYS = *Amanda::Configc::CNF_SSH_KEYS;
*CNF_AMANDAD_PATH = *Amanda::Configc::CNF_AMANDAD_PATH;
*CNF_CLIENT_USERNAME = *Amanda::Configc::CNF_CLIENT_USERNAME;
*CNF_GNUTAR_LIST_DIR = *Amanda::Configc::CNF_GNUTAR_LIST_DIR;
*CNF_AMANDATES = *Amanda::Configc::CNF_AMANDATES;
*CNF_MAILTO = *Amanda::Configc::CNF_MAILTO;
*CNF_DUMPUSER = *Amanda::Configc::CNF_DUMPUSER;
*CNF_TAPEDEV = *Amanda::Configc::CNF_TAPEDEV;
*CNF_DEVICE_PROPERTY = *Amanda::Configc::CNF_DEVICE_PROPERTY;
*CNF_CHANGERDEV = *Amanda::Configc::CNF_CHANGERDEV;
*CNF_CHANGERFILE = *Amanda::Configc::CNF_CHANGERFILE;
*CNF_LABELSTR = *Amanda::Configc::CNF_LABELSTR;
*CNF_TAPELIST = *Amanda::Configc::CNF_TAPELIST;
*CNF_DISKFILE = *Amanda::Configc::CNF_DISKFILE;
*CNF_INFOFILE = *Amanda::Configc::CNF_INFOFILE;
*CNF_LOGDIR = *Amanda::Configc::CNF_LOGDIR;
*CNF_INDEXDIR = *Amanda::Configc::CNF_INDEXDIR;
*CNF_TAPETYPE = *Amanda::Configc::CNF_TAPETYPE;
*CNF_DUMPCYCLE = *Amanda::Configc::CNF_DUMPCYCLE;
*CNF_RUNSPERCYCLE = *Amanda::Configc::CNF_RUNSPERCYCLE;
*CNF_TAPECYCLE = *Amanda::Configc::CNF_TAPECYCLE;
*CNF_NETUSAGE = *Amanda::Configc::CNF_NETUSAGE;
*CNF_INPARALLEL = *Amanda::Configc::CNF_INPARALLEL;
*CNF_DUMPORDER = *Amanda::Configc::CNF_DUMPORDER;
*CNF_BUMPPERCENT = *Amanda::Configc::CNF_BUMPPERCENT;
*CNF_BUMPSIZE = *Amanda::Configc::CNF_BUMPSIZE;
*CNF_BUMPMULT = *Amanda::Configc::CNF_BUMPMULT;
*CNF_BUMPDAYS = *Amanda::Configc::CNF_BUMPDAYS;
*CNF_TPCHANGER = *Amanda::Configc::CNF_TPCHANGER;
*CNF_RUNTAPES = *Amanda::Configc::CNF_RUNTAPES;
*CNF_MAXDUMPS = *Amanda::Configc::CNF_MAXDUMPS;
*CNF_ETIMEOUT = *Amanda::Configc::CNF_ETIMEOUT;
*CNF_DTIMEOUT = *Amanda::Configc::CNF_DTIMEOUT;
*CNF_CTIMEOUT = *Amanda::Configc::CNF_CTIMEOUT;
*CNF_TAPEBUFS = *Amanda::Configc::CNF_TAPEBUFS;
*CNF_DEVICE_OUTPUT_BUFFER_SIZE = *Amanda::Configc::CNF_DEVICE_OUTPUT_BUFFER_SIZE;
*CNF_PRINTER = *Amanda::Configc::CNF_PRINTER;
*CNF_AUTOFLUSH = *Amanda::Configc::CNF_AUTOFLUSH;
*CNF_RESERVE = *Amanda::Configc::CNF_RESERVE;
*CNF_MAXDUMPSIZE = *Amanda::Configc::CNF_MAXDUMPSIZE;
*CNF_COLUMNSPEC = *Amanda::Configc::CNF_COLUMNSPEC;
*CNF_AMRECOVER_DO_FSF = *Amanda::Configc::CNF_AMRECOVER_DO_FSF;
*CNF_AMRECOVER_CHECK_LABEL = *Amanda::Configc::CNF_AMRECOVER_CHECK_LABEL;
*CNF_AMRECOVER_CHANGER = *Amanda::Configc::CNF_AMRECOVER_CHANGER;
*CNF_TAPERALGO = *Amanda::Configc::CNF_TAPERALGO;
*CNF_FLUSH_THRESHOLD_DUMPED = *Amanda::Configc::CNF_FLUSH_THRESHOLD_DUMPED;
*CNF_FLUSH_THRESHOLD_SCHEDULED = *Amanda::Configc::CNF_FLUSH_THRESHOLD_SCHEDULED;
*CNF_TAPERFLUSH = *Amanda::Configc::CNF_TAPERFLUSH;
*CNF_DISPLAYUNIT = *Amanda::Configc::CNF_DISPLAYUNIT;
*CNF_KRB5KEYTAB = *Amanda::Configc::CNF_KRB5KEYTAB;
*CNF_KRB5PRINCIPAL = *Amanda::Configc::CNF_KRB5PRINCIPAL;
*CNF_LABEL_NEW_TAPES = *Amanda::Configc::CNF_LABEL_NEW_TAPES;
*CNF_USETIMESTAMPS = *Amanda::Configc::CNF_USETIMESTAMPS;
*CNF_REP_TRIES = *Amanda::Configc::CNF_REP_TRIES;
*CNF_CONNECT_TRIES = *Amanda::Configc::CNF_CONNECT_TRIES;
*CNF_REQ_TRIES = *Amanda::Configc::CNF_REQ_TRIES;
*CNF_DEBUG_AMANDAD = *Amanda::Configc::CNF_DEBUG_AMANDAD;
*CNF_DEBUG_AMIDXTAPED = *Amanda::Configc::CNF_DEBUG_AMIDXTAPED;
*CNF_DEBUG_AMINDEXD = *Amanda::Configc::CNF_DEBUG_AMINDEXD;
*CNF_DEBUG_AMRECOVER = *Amanda::Configc::CNF_DEBUG_AMRECOVER;
*CNF_DEBUG_AUTH = *Amanda::Configc::CNF_DEBUG_AUTH;
*CNF_DEBUG_EVENT = *Amanda::Configc::CNF_DEBUG_EVENT;
*CNF_DEBUG_HOLDING = *Amanda::Configc::CNF_DEBUG_HOLDING;
*CNF_DEBUG_PROTOCOL = *Amanda::Configc::CNF_DEBUG_PROTOCOL;
*CNF_DEBUG_PLANNER = *Amanda::Configc::CNF_DEBUG_PLANNER;
*CNF_DEBUG_DRIVER = *Amanda::Configc::CNF_DEBUG_DRIVER;
*CNF_DEBUG_DUMPER = *Amanda::Configc::CNF_DEBUG_DUMPER;
*CNF_DEBUG_CHUNKER = *Amanda::Configc::CNF_DEBUG_CHUNKER;
*CNF_DEBUG_TAPER = *Amanda::Configc::CNF_DEBUG_TAPER;
*CNF_DEBUG_SELFCHECK = *Amanda::Configc::CNF_DEBUG_SELFCHECK;
*CNF_DEBUG_SENDSIZE = *Amanda::Configc::CNF_DEBUG_SENDSIZE;
*CNF_DEBUG_SENDBACKUP = *Amanda::Configc::CNF_DEBUG_SENDBACKUP;
*CNF_RESERVED_UDP_PORT = *Amanda::Configc::CNF_RESERVED_UDP_PORT;
*CNF_RESERVED_TCP_PORT = *Amanda::Configc::CNF_RESERVED_TCP_PORT;
*CNF_UNRESERVED_TCP_PORT = *Amanda::Configc::CNF_UNRESERVED_TCP_PORT;
*TAPETYPE_COMMENT = *Amanda::Configc::TAPETYPE_COMMENT;
*TAPETYPE_LBL_TEMPL = *Amanda::Configc::TAPETYPE_LBL_TEMPL;
*TAPETYPE_BLOCKSIZE = *Amanda::Configc::TAPETYPE_BLOCKSIZE;
*TAPETYPE_READBLOCKSIZE = *Amanda::Configc::TAPETYPE_READBLOCKSIZE;
*TAPETYPE_LENGTH = *Amanda::Configc::TAPETYPE_LENGTH;
*TAPETYPE_FILEMARK = *Amanda::Configc::TAPETYPE_FILEMARK;
*TAPETYPE_SPEED = *Amanda::Configc::TAPETYPE_SPEED;
*TAPETYPE_FILE_PAD = *Amanda::Configc::TAPETYPE_FILE_PAD;
*DUMPTYPE_COMMENT = *Amanda::Configc::DUMPTYPE_COMMENT;
*DUMPTYPE_PROGRAM = *Amanda::Configc::DUMPTYPE_PROGRAM;
*DUMPTYPE_SRVCOMPPROG = *Amanda::Configc::DUMPTYPE_SRVCOMPPROG;
*DUMPTYPE_CLNTCOMPPROG = *Amanda::Configc::DUMPTYPE_CLNTCOMPPROG;
*DUMPTYPE_SRV_ENCRYPT = *Amanda::Configc::DUMPTYPE_SRV_ENCRYPT;
*DUMPTYPE_CLNT_ENCRYPT = *Amanda::Configc::DUMPTYPE_CLNT_ENCRYPT;
*DUMPTYPE_AMANDAD_PATH = *Amanda::Configc::DUMPTYPE_AMANDAD_PATH;
*DUMPTYPE_CLIENT_USERNAME = *Amanda::Configc::DUMPTYPE_CLIENT_USERNAME;
*DUMPTYPE_SSH_KEYS = *Amanda::Configc::DUMPTYPE_SSH_KEYS;
*DUMPTYPE_SECURITY_DRIVER = *Amanda::Configc::DUMPTYPE_SECURITY_DRIVER;
*DUMPTYPE_EXCLUDE = *Amanda::Configc::DUMPTYPE_EXCLUDE;
*DUMPTYPE_INCLUDE = *Amanda::Configc::DUMPTYPE_INCLUDE;
*DUMPTYPE_PRIORITY = *Amanda::Configc::DUMPTYPE_PRIORITY;
*DUMPTYPE_DUMPCYCLE = *Amanda::Configc::DUMPTYPE_DUMPCYCLE;
*DUMPTYPE_MAXDUMPS = *Amanda::Configc::DUMPTYPE_MAXDUMPS;
*DUMPTYPE_MAXPROMOTEDAY = *Amanda::Configc::DUMPTYPE_MAXPROMOTEDAY;
*DUMPTYPE_BUMPPERCENT = *Amanda::Configc::DUMPTYPE_BUMPPERCENT;
*DUMPTYPE_BUMPSIZE = *Amanda::Configc::DUMPTYPE_BUMPSIZE;
*DUMPTYPE_BUMPDAYS = *Amanda::Configc::DUMPTYPE_BUMPDAYS;
*DUMPTYPE_BUMPMULT = *Amanda::Configc::DUMPTYPE_BUMPMULT;
*DUMPTYPE_STARTTIME = *Amanda::Configc::DUMPTYPE_STARTTIME;
*DUMPTYPE_STRATEGY = *Amanda::Configc::DUMPTYPE_STRATEGY;
*DUMPTYPE_ESTIMATE = *Amanda::Configc::DUMPTYPE_ESTIMATE;
*DUMPTYPE_COMPRESS = *Amanda::Configc::DUMPTYPE_COMPRESS;
*DUMPTYPE_ENCRYPT = *Amanda::Configc::DUMPTYPE_ENCRYPT;
*DUMPTYPE_SRV_DECRYPT_OPT = *Amanda::Configc::DUMPTYPE_SRV_DECRYPT_OPT;
*DUMPTYPE_CLNT_DECRYPT_OPT = *Amanda::Configc::DUMPTYPE_CLNT_DECRYPT_OPT;
*DUMPTYPE_COMPRATE = *Amanda::Configc::DUMPTYPE_COMPRATE;
*DUMPTYPE_TAPE_SPLITSIZE = *Amanda::Configc::DUMPTYPE_TAPE_SPLITSIZE;
*DUMPTYPE_FALLBACK_SPLITSIZE = *Amanda::Configc::DUMPTYPE_FALLBACK_SPLITSIZE;
*DUMPTYPE_SPLIT_DISKBUFFER = *Amanda::Configc::DUMPTYPE_SPLIT_DISKBUFFER;
*DUMPTYPE_RECORD = *Amanda::Configc::DUMPTYPE_RECORD;
*DUMPTYPE_SKIP_INCR = *Amanda::Configc::DUMPTYPE_SKIP_INCR;
*DUMPTYPE_SKIP_FULL = *Amanda::Configc::DUMPTYPE_SKIP_FULL;
*DUMPTYPE_HOLDINGDISK = *Amanda::Configc::DUMPTYPE_HOLDINGDISK;
*DUMPTYPE_KENCRYPT = *Amanda::Configc::DUMPTYPE_KENCRYPT;
*DUMPTYPE_IGNORE = *Amanda::Configc::DUMPTYPE_IGNORE;
*DUMPTYPE_INDEX = *Amanda::Configc::DUMPTYPE_INDEX;
*INTER_COMMENT = *Amanda::Configc::INTER_COMMENT;
*INTER_MAXUSAGE = *Amanda::Configc::INTER_MAXUSAGE;
*HOLDING_COMMENT = *Amanda::Configc::HOLDING_COMMENT;
*HOLDING_DISKDIR = *Amanda::Configc::HOLDING_DISKDIR;
*HOLDING_DISKSIZE = *Amanda::Configc::HOLDING_DISKSIZE;
*HOLDING_CHUNKSIZE = *Amanda::Configc::HOLDING_CHUNKSIZE;
*HOLD_NEVER = *Amanda::Configc::HOLD_NEVER;
*HOLD_AUTO = *Amanda::Configc::HOLD_AUTO;
*HOLD_REQUIRED = *Amanda::Configc::HOLD_REQUIRED;
*COMP_NONE = *Amanda::Configc::COMP_NONE;
*COMP_FAST = *Amanda::Configc::COMP_FAST;
*COMP_BEST = *Amanda::Configc::COMP_BEST;
*COMP_CUST = *Amanda::Configc::COMP_CUST;
*COMP_SERVER_FAST = *Amanda::Configc::COMP_SERVER_FAST;
*COMP_SERVER_BEST = *Amanda::Configc::COMP_SERVER_BEST;
*COMP_SERVER_CUST = *Amanda::Configc::COMP_SERVER_CUST;
*ENCRYPT_NONE = *Amanda::Configc::ENCRYPT_NONE;
*ENCRYPT_CUST = *Amanda::Configc::ENCRYPT_CUST;
*ENCRYPT_SERV_CUST = *Amanda::Configc::ENCRYPT_SERV_CUST;
*DS_SKIP = *Amanda::Configc::DS_SKIP;
*DS_STANDARD = *Amanda::Configc::DS_STANDARD;
*DS_NOFULL = *Amanda::Configc::DS_NOFULL;
*DS_NOINC = *Amanda::Configc::DS_NOINC;
*DS_4 = *Amanda::Configc::DS_4;
*DS_5 = *Amanda::Configc::DS_5;
*DS_HANOI = *Amanda::Configc::DS_HANOI;
*DS_INCRONLY = *Amanda::Configc::DS_INCRONLY;
*ES_CLIENT = *Amanda::Configc::ES_CLIENT;
*ES_SERVER = *Amanda::Configc::ES_SERVER;
*ES_CALCSIZE = *Amanda::Configc::ES_CALCSIZE;
*ALGO_FIRST = *Amanda::Configc::ALGO_FIRST;
*ALGO_FIRSTFIT = *Amanda::Configc::ALGO_FIRSTFIT;
*ALGO_LARGEST = *Amanda::Configc::ALGO_LARGEST;
*ALGO_LARGESTFIT = *Amanda::Configc::ALGO_LARGESTFIT;
*ALGO_SMALLEST = *Amanda::Configc::ALGO_SMALLEST;
*ALGO_LAST = *Amanda::Configc::ALGO_LAST;
*debug_amandad = *Amanda::Configc::debug_amandad;
*debug_amidxtaped = *Amanda::Configc::debug_amidxtaped;
*debug_amindexd = *Amanda::Configc::debug_amindexd;
*debug_amrecover = *Amanda::Configc::debug_amrecover;
*debug_auth = *Amanda::Configc::debug_auth;
*debug_event = *Amanda::Configc::debug_event;
*debug_holding = *Amanda::Configc::debug_holding;
*debug_protocol = *Amanda::Configc::debug_protocol;
*debug_planner = *Amanda::Configc::debug_planner;
*debug_driver = *Amanda::Configc::debug_driver;
*debug_dumper = *Amanda::Configc::debug_dumper;
*debug_chunker = *Amanda::Configc::debug_chunker;
*debug_taper = *Amanda::Configc::debug_taper;
*debug_selfcheck = *Amanda::Configc::debug_selfcheck;
*debug_sendsize = *Amanda::Configc::debug_sendsize;
*debug_sendbackup = *Amanda::Configc::debug_sendbackup;
*CONFIG_INIT_EXPLICIT_NAME = *Amanda::Configc::CONFIG_INIT_EXPLICIT_NAME;
*CONFIG_INIT_USE_CWD = *Amanda::Configc::CONFIG_INIT_USE_CWD;
*CONFIG_INIT_CLIENT = *Amanda::Configc::CONFIG_INIT_CLIENT;
*CONFIG_INIT_OVERLAY = *Amanda::Configc::CONFIG_INIT_OVERLAY;
*CONFIG_INIT_FATAL = *Amanda::Configc::CONFIG_INIT_FATAL;

@EXPORT_OK = ();
%EXPORT_TAGS = ();

=head1 NAME

Amanda::Config - access to Amanda configuration parameters

=head1 SYNOPSIS

  use Amanda::Config qw( :init :getconf );

  config_init($CONFIG_INIT_EXPLICIT_NAME, $ARGV[1])
    or die("errors processing config file " . $Amanda::Config::get_config_filename());

  print "tape device is ", getconf($CNF_TAPEDEV), "\n";

This API closely parallels the C API.  See L<conffile.h> for details
on the functions and constants available here.

=head1 API STATUS

Stable

=head1 INITIALIZATION

The Amanda configuration is treated as a global state for the
application.  It is not possible to load two configurations
simultaneously.

All initialization-related symbols can be imported with the tag
C<:init>.

=head2 LOADING CONFIGURATION

The Amanda configuration is loaded with the aptly named
C<config_init($flags, $name)>.  Because of the great variety in
invocation method among Amanda applications, this function has a number
of flags that affect its behavior.  These flags can be OR'd together.

=over

=item If C<CONFIG_INIT_EXPLICIT_NAME> is given, then the C<$name>
parameter can contain the name of a configuration to load.

=item If C<CONFIG_INIT_USE_CWD> is given, and if the current directory
contains C<amanda.conf>, then that file is loaded.

=item If C<CONFIG_INIT_CLIENT> is given, then a client configuration
is loaded.

=item If C<CONFIG_INIT_OVERLAY> is given, then any existing
configuration is not reset.

=item If C<CONFIG_INIT_FATAL> is given, then any errors are considered
fatal, and C<config_init> does not return.

=back

See C<conffile.h> for more detailed information on these flags and
their interactions.

C<config_uninit()> reverses the effects of C<config_init>.  It is
not often used.

Once the configuration is loaded, the configuration name
(e.g., "DailySet1"), directory (C</etc/amanda/DailySet1>),
and filename (C</etc/amanda/DailySet1/amanda.conf>) are
available from C<get_config_name()>, C<get_config_dir()>, and
C<get_config_filename()>, respectively.

=head2 CONFIG OVERWRITES

Most Amanda applications accept the command-line option C<-o>
to "overwrite" configuration values in C<amanda.conf>.  In Perl
applications, these options should be parsed with L<Getopt::Long>, with
the action being a call to C<add_config_overwrite_opt>.  For example:

  my $config_overwrites = new_config_overwrites($#ARGV+1);
    GetOptions(
	# ...
	'o=s' => sub { add_config_overwrite_opt($config_overwrites, $_[1]); },
    ) or usage();
  my $cfg_ok = config_init($CONFIG_INIT_EXPLICIT_NAME | $CONFIG_INIT_USE_CWD, $config_name);
  apply_config_overwrites($config_overwrites);

C<new_config_overwrites($size_estimate)> creates a new
overwrites object, using the given size as an estimate of
the number of items it will contain (C<$#ARGC/2> is a good
estimate).  Individual configuration options are then added via
C<add_config_overwrite($co, $key, $value)> (which takes a key/value
pair) or C<add_config_overwrite_opt($co, $optarg)>, which parses a
string following C<-o> on the command line.

Once the overwrites are gathered, they are applied with
C<apply_config_overwrites($co)>, which applies the overwrites to the
active configuration.  No further operations can be performed on the
overwrites object after C<apply_config_overwrites> has been called.

The utility function C<get_config_options()> returns a list of
command-line arguments to represent any overwrites that were used
to generate the current configuration.  (TODO: this function isn't
available yet)

=head1 PARAMETER ACCESS

Amanda configurations consist of "global" parameters and several
sets of "subsections" -- one set for dumptypes, one for tapetypes,
and so on.

All of the global parameters are represented by a constant beginning
with C<$CNF_>, e.g., C<$CNF_LABELSTR>.  The function C<getconf($cnf)>
returns the value of parameter C<$cnf>, in whatever format is
appropriate for the parameter.  C<getconf_seen($cnf)> returns a true
value if C<$cnf> was seen in the configuration file.  If it was not
seen, then it will have its default value.

Some parameters have enumerated types.  The values for those
enumerations are available from this module with the same name as
in C<conffile.h>.  For example, C<$CNF_TAPERALGO> will yield a value
from the enumeration C<taperalgo_t>, the constants for which all
begin with C<$ALGO_>.  See C<conffile.h> for the details.

Each subsection type has the following functions:

=over

=item C<lookup_TYP($subsec_name)>, which returns an opaque object
(C<$ss>) representing the subsection, or C<undef> if no subsection
with that name exists;

=item C<TYP_name($ss)>, returning the name of the subsection;

=item C<TYP_getconf($ss, $cnf)>, which fetches a parameter value from
C<$ss>; and

=item C<TYP_seen($ss, $cnf)>, which returns a true value if <$cnf>