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NAME
    Config::General - Generic Config Module

SYNOPSIS
     #
     # the OOP way
     use Config::General;
     $conf = Config::General->new("rcfile");
     my %config = $conf->getall;

     #
     # the procedural way
     use Config::General qw(ParseConfig SaveConfig SaveConfigString);
     my %config = ParseConfig("rcfile");

DESCRIPTION
    This module opens a config file and parses its contents for you. The new method requires one
    parameter which needs to be a filename. The method getall returns a hash which contains all
    options and its associated values of your config file.

    The format of config files supported by Config::General is inspired by the well known Apache
    config format, in fact, this module is 100% compatible to Apache configs, but you can also just
    use simple name/value pairs in your config files.

    In addition to the capabilities of an Apache config file it supports some enhancements such as
    here-documents, C-style comments or multiline options.

SUBROUTINES/METHODS
    new()
        Possible ways to call new():

         $conf = Config::General->new("rcfile");

         $conf = Config::General->new(\%somehash);

         $conf = Config::General->new( %options ); # see below for description of possible options

        This method returns a Config::General object (a hash blessed into "Config::General"
        namespace. All further methods must be used from that returned object. see below.

        You can use the new style with hash parameters or the old style which is of course still
        supported. Possible parameters to new() are:

        * a filename of a configfile, which will be opened and parsed by the parser

        or

        * a hash reference, which will be used as the config.

        An alternative way to call new() is supplying an option- hash with one or more of the
        following keys set:

        -ConfigFile
            A filename or a filehandle, i.e.:

             -ConfigFile => "rcfile" or -ConfigFile => \$FileHandle

        -ConfigHash
            A hash reference, which will be used as the config, i.e.:

             -ConfigHash => \%somehash

        -String
            A string which contains a whole config, or an arrayref containing the whole config line
            by line. The parser will parse the contents of the string instead of a file. i.e:

             -String => $complete_config

            it is also possible to feed an array reference to -String:

             -String => \@config_lines

        -AllowMultiOptions
            If the value is "no", then multiple identical options are disallowed. The default is
            "yes". i.e.:

             -AllowMultiOptions => "yes"

            see IDENTICAL OPTIONS for details.

        -LowerCaseNames
            If set to a true value, then all options found in the config will be converted to
            lowercase. This allows you to provide case-in-sensitive configs. The values of the
            options will not lowercased.

        -UseApacheInclude
            If set to a true value, the parser will consider "include ..." as valid include
            statement (just like the well known Apache include statement).

            It also supports apache's "IncludeOptional" statement with the same behavior, that is,
            if the include file doesn't exist no error will be thrown.

        -IncludeRelative
            If set to a true value, included files with a relative path (i.e. "cfg/blah.conf") will
            be opened from within the location of the configfile instead from within the location of
            the script($0). This works only if the configfile has a absolute pathname (i.e.
            "/etc/main.conf").

            If the variable -ConfigPath has been set and if the file to be included could not be
            found in the location relative to the current config file, the module will search within
            -ConfigPath for the file. See the description of -ConfigPath for more details.

        -IncludeDirectories
            If set to a true value, you may specify include a directory, in which case all files
            inside the directory will be loaded in ASCII order. Directory includes will not recurse
            into subdirectories. This is comparable to including a directory in Apache-style config
            files.

        -IncludeGlob
            If set to a true value, you may specify a glob pattern for an include to include all
            matching files (e.g. <<include conf.d/*.conf>>). Also note that as with standard file
            patterns, * will not match dot-files, so <<include dir/*>> is often more desirable than
            including a directory with -IncludeDirectories.

            An include option will not cause a parser error if the glob didn't return anything.

        -IncludeAgain
            If set to a true value, you will be able to include a sub-configfile multiple times.
            With the default, false, you will get a warning about duplicate includes and only the
            first include will succeed.

            Reincluding a configfile can be useful if it contains data that you want to be present
            in multiple places in the data tree. See the example under "INCLUDES".

            Note, however, that there is currently no check for include recursion.

        -ConfigPath
            As mentioned above, you can use this variable to specify a search path for relative
            config files which have to be included. Config::General will search within this path for
            the file if it cannot find the file at the location relative to the current config file.

            To provide multiple search paths you can specify an array reference for the path. For
            example:

             @path = qw(/usr/lib/perl /nfs/apps/lib /home/lib);
             ..
             -ConfigPath => \@path

        -MergeDuplicateBlocks
            If set to a true value, then duplicate blocks, that means blocks and named blocks, will
            be merged into a single one (see below for more details on this). The default behavior
            of Config::General is to create an array if some junk in a config appears more than
            once.

        -MergeDuplicateOptions
            If set to a true value, then duplicate options will be merged. That means, if the same
            option occurs more than once, the last one will be used in the resulting config hash.

            Setting this option implies -AllowMultiOptions == false unless you set
            -AllowMultiOptions explicit to 'true'. In this case duplicate blocks are allowed and put
            into an array but duplicate options will be merged.

        -AutoLaunder
            If set to a true value, then all values in your config file will be laundered to allow
            them to be used under a -T taint flag. This could be regarded as circumventing the
            purpose of the -T flag, however, if the bad guys can mess with your config file, you
            have problems that -T will not be able to stop. AutoLaunder will only handle a config
            file being read from -ConfigFile.

        -AutoTrue
            If set to a true value, then options in your config file, whose values are set to true
            or false values, will be normalised to 1 or 0 respectively.

            The following values will be considered as true:

             yes, on, 1, true

            The following values will be considered as false:

             no, off, 0, false

            This effect is case-insensitive, i.e. both "Yes" or "No" will result in 1.

        -FlagBits
            This option takes one required parameter, which must be a hash reference.

            The supplied hash reference needs to define variables for which you want to preset
            values. Each variable you have defined in this hash-ref and which occurs in your config
            file, will cause this variable being set to the preset values to which the value in the
            config file refers to.

            Multiple flags can be used, separated by the pipe character |.

            Well, an example will clarify things:

             my $conf = Config::General->new(
                     -ConfigFile => "rcfile",
                     -FlagBits => {
                          Mode => {
                             CLEAR    => 1,
                             STRONG   => 1,
                             UNSECURE => "32bit" }
                     }
             );

            In this example we are defining a variable named *"Mode"* which may contain one or more
            of "CLEAR", "STRONG" and "UNSECURE" as value.

            The appropriate config entry may look like this:

             # rcfile
             Mode = CLEAR | UNSECURE

            The parser will create a hash which will be the value of the key "Mode". This hash will
            contain all flags which you have pre-defined, but only those which were set in the
            config will contain the pre-defined value, the other ones will be undefined.

            The resulting config structure would look like this after parsing:

             %config = (
                         Mode => {
                                   CLEAR    => 1,
                                   UNSECURE => "32bit",
                                   STRONG   => undef,
                                 }
                       );

            This method allows the user (or, the "maintainer" of the configfile for your
            application) to set multiple pre-defined values for one option.

            Please beware, that all occurrences of those variables will be handled this way, there
            is no way to distinguish between variables in different scopes. That means, if "Mode"
            would also occur inside a named block, it would also parsed this way.

            Values which are not defined in the hash-ref supplied to the parameter -FlagBits and
            used in the corresponding variable in the config will be ignored.

            Example:

             # rcfile
             Mode = BLAH | CLEAR

            would result in this hash structure:

              %config = (
                         Mode => {
                                   CLEAR    => 1,
                                   UNSECURE => undef,
                                   STRONG   => undef,
                                 }
                       );

            "BLAH" will be ignored silently.

        -DefaultConfig
            This can be a hash reference or a simple scalar (string) of a config. This causes the
            module to preset the resulting config hash with the given values, which allows you to
            set default values for particular config options directly.

            Note that you probably want to use this with -MergeDuplicateOptions, otherwise a default
            value already in the configuration file will produce an array of two values.

        -Tie
            -Tie takes the name of a Tie class as argument that each new hash should be based off
            of.

            This hash will be used as the 'backing hash' instead of a standard Perl hash, which
            allows you to affect the way, variable storing will be done. You could, for example
            supply a tied hash, say Tie::DxHash, which preserves ordering of the keys in the config
            (which a standard Perl hash won't do). Or, you could supply a hash tied to a DBM file to
            save the parsed variables to disk.

            There are many more things to do in tie-land, see tie to get some interesting ideas.

            If you want to use the -Tie feature together with -DefaultConfig make sure that the hash
            supplied to -DefaultConfig must be tied to the same Tie class.

            Make sure that the hash which receives the generated hash structure (e.g. which you are
            using in the assignment: %hash = $config->getall()) must be tied to the same Tie class.

            Example:

             use Config::General qw(ParseConfig);
             use Tie::IxHash;
             tie my %hash, "Tie::IxHash";
             %hash = ParseConfig(
                       -ConfigFile => shift(),
                       -Tie => "Tie::IxHash"
                     );

        -InterPolateVars
            If set to a true value, variable interpolation will be done on your config input. See
            Config::General::Interpolated for more information.

        -InterPolateEnv
            If set to a true value, environment variables can be used in configs.

            This implies -InterPolateVars.

        -AllowSingleQuoteInterpolation
            By default variables inside single quotes will not be interpolated. If you turn on this
            option, they will be interpolated as well.

        -ExtendedAccess
            If set to a true value, you can use object oriented (extended) methods to access the
            parsed config. See Config::General::Extended for more information.

        -StrictObjects
            By default this is turned on, which causes Config::General to croak with an error if you
            try to access a non-existent key using the OOP-way (-ExtendedAcess enabled). If you turn
            -StrictObjects off (by setting to 0 or "no") it will just return an empty
            object/hash/scalar. This is valid for OOP-access 8via AUTOLOAD and for the methods
            obj(), hash() and value().

        -StrictVars
            By default this is turned on, which causes Config::General to croak with an error if an
            undefined variable with InterPolateVars turned on occurs in a config. Set to *false*
            (i.e. 0) to avoid such error messages.

        -SplitPolicy
            You can influence the way how Config::General decides which part of a line in a config
            file is the key and which one is the value. By default it tries its best to guess. That
            means you can mix equalsign assignments and whitespace assignments.

            However, sometime you may wish to make it more strictly for some reason. In this case
            you can set -SplitPolicy. The possible values are: 'guess' which is the default,
            'whitespace' which causes the module to split by whitespace, 'equalsign' which causes it
            to split strictly by equal sign, or 'custom'. In the latter case you must also set
            -SplitDelimiter to some regular expression of your choice. For example:

             -SplitDelimiter => '\s*:\s*'

            will cause the module to split by colon while whitespace which surrounds the delimiter
            will be removed.

            Please note that the delimiter used when saving a config (save_file() or save_string())
            will be chosen according to the current -SplitPolicy. If -SplitPolicy is set to 'guess'
            or 'whitespace', 3 spaces will be used to delimit saved options. If 'custom' is set,
            then you need to set -StoreDelimiter.

        -SplitDelimiter
            Set this to any arbitrary regular expression which will be used for option/value
            splitting. -SplitPolicy must be set to 'custom' to make this work.

        -StoreDelimiter
            You can use this parameter to specify a custom delimiter to use when saving configs to a
            file or string. You only need to set it if you want to store the config back to disk and
            if you have -SplitPolicy set to 'custom'.

            However, this parameter takes precedence over whatever is set for -SplitPolicy.

            Be very careful with this parameter.

        -CComments
            Config::General is able to notice c-style comments (see section COMMENTS). But for some
            reason you might no need this. In this case you can turn this feature off by setting
            -CComments to a false value('no', 0, 'off').

            By default -CComments is turned on.

        -BackslashEscape
            Deprecated Option.

        -SlashIsDirectory
            If you turn on this parameter, a single slash as the last character of a named block
            will be considered as a directory name.

            By default this flag is turned off, which makes the module somewhat incompatible to
            Apache configs, since such a setup will be normally considered as an explicit empty
            block, just as XML defines it.

            For example, if you have the following config:

             <Directory />
               Index index.awk
             </Directory>

            you will get such an error message from the parser:

             EndBlock "</Directory>" has no StartBlock statement (level: 1, chunk 10)!

            This is caused by the fact that the config chunk below will be internally converted to:

             <Directory></Directory>
               Index index.awk
             </Directory>

            Now there is one '</Directory>' too much. The proper solution is to use quotation to
            circumvent this error:

             <Directory "/">
               Index index.awk
             </Directory>

            However, a raw apache config comes without such quotes. In this case you may consider to
            turn on -SlashIsDirectory.

            Please note that this is a new option (incorporated in version 2.30), it may lead to
            various unexpected side effects or other failures. You've been warned.

        -UseApacheIfDefine
            Enables support for Apache <IfDefine> ... </IfDefine>. See -Define.

        -Define
            Defines the symbols to be used for conditional configuration files. Allowed arguments:
            scalar, scalar ref, array ref or hash ref.

            Examples:

             -Define => 'TEST'
             -Define => \$testOrProduction
             -Define => [qw(TEST VERBOSE)]
             -Define => {TEST => 1, VERBOSE => 1}

            Sample configuration:

              <Logging>
                <IfDefine TEST>
                   Level Debug
                   include test/*.cfg
                </IfDef>
                <IfDefine !TEST>
                  Level Notice
                   include production/*.cfg
                </IfDefine>
              </Logging>

        -ApacheCompatible
            Over the past years a lot of options has been incorporated into Config::General to be
            able to parse real Apache configs.

            The new -ApacheCompatible option now makes it possible to tweak all options in a way
            that Apache configs can be parsed.

            This is called "apache compatibility mode" - if you will ever have problems with parsing
            Apache configs without this option being set, you'll get no help by me. Thanks :)

            The following options will be set:

             UseApacheInclude   = 1
             IncludeRelative    = 1
             IncludeDirectories = 1
             IncludeGlob        = 1
             SlashIsDirectory   = 1
             SplitPolicy        = 'whitespace'
             CComments          = 0
             UseApacheIfDefine  = 1

            Take a look into the particular documentation sections what those options are doing.

            Beside setting some options it also turns off support for explicit empty blocks.

        -UTF8
            If turned on, all files will be opened in utf8 mode. This may not work properly with
            older versions of Perl.

        -SaveSorted
            If you want to save configs in a sorted manner, turn this parameter on. It is not
            enabled by default.

        -NoEscape
            If you want to use the data ( scalar or final leaf ) without escaping special character,
            turn this parameter on. It is not enabled by default.

        -NormalizeBlock
            Takes a subroutine reference as parameter and gets the current block or blockname passed
            as parameter and is expected to return it in some altered way as a scalar string. The
            sub will be called before anything else will be done by the module itself (e.g.
            interpolation).

            Example:

             -NormalizeBlock => sub { my $x = shift; $x =~ s/\s*$//; $x; }

            This removes trailing whitespaces of block names.

        -NormalizeOption
            Same as -NormalizeBlock but applied on options only.

        -NormalizeValue
            Same as -NormalizeBlock but applied on values only.

    getall()
        Returns a hash structure which represents the whole config.

    files()
        Returns a list of all files read in.

    save_file()
        Writes the config hash back to the hard disk. This method takes one or two parameters. The
        first parameter must be the filename where the config should be written to. The second
        parameter is optional, it must be a reference to a hash structure, if you set it. If you do
        not supply this second parameter then the internal config hash, which has already been
        parsed, will be used.

        Please note that any occurrence of comments will be ignored by getall() and thus be lost
        after you call this method.

        You need also to know that named blocks will be converted to nested blocks (which is the
        same from the perl point of view). An example:

         <user hans>
           id 13
         </user>

        will become the following after saving:

         <user>
           <hans>
              id 13
           </hans>
         </user>

        Example:

         $conf_obj->save_file("newrcfile", \%config);

        or, if the config has already been parsed, or if it didn't change:

         $conf_obj->save_file("newrcfile");

    save_string()
        This method is equivalent to the previous save_file(), but it does not store the generated
        config to a file. Instead it returns it as a string, which you can save yourself afterwards.

        It takes one optional parameter, which must be a reference to a hash structure. If you omit
        this parameter, the internal config hash, which has already been parsed, will be used.

        Example:

         my $content = $conf_obj->save_string(\%config);

        or:

         my $content = $conf_obj->save_string();

CONFIG FILE FORMAT
    Lines beginning with # and empty lines will be ignored. (see section COMMENTS!) Spaces at the
    beginning and the end of a line will also be ignored as well as tabulators. If you need spaces
    at the end or the beginning of a value you can surround it with double quotes. An option line
    starts with its name followed by a value. An equal sign is optional. Some possible examples:

     user    max
     user  = max
     user            max

    If there are more than one statements with the same name, it will create an array instead of a
    scalar. See the example below.

    The method getall returns a hash of all values.

BLOCKS
    You can define a block of options. A block looks much like a block in the wellknown Apache
    config format. It starts with <blockname> and ends with </blockname>.

    A block start and end cannot be on the same line.

    An example:

     <database>
      host   = muli
      user   = moare
      dbname = modb
      dbpass = D4r_9Iu
     </database>

    Blocks can also be nested. Here is a more complicated example:

     user   = hans
     server = mc200
     db     = maxis
     passwd = D3rf$
     <jonas>
      user    = tom
      db      = unknown
      host    = mila
      <tablestructure>
       index   int(100000)
       name    char(100)
       prename char(100)
       city    char(100)
       status  int(10)
       allowed moses
       allowed ingram
       allowed joice
      </tablestructure>
     </jonas>

    The hash which the method getall returns look like that:

      print Data::Dumper(\%hash);
      $VAR1 = {
               'passwd' => 'D3rf$',
               'jonas'  => {
                            'tablestructure' => {
                                                 'prename' => 'char(100)',
                                                 'index'   => 'int(100000)',
                                                 'city'    => 'char(100)',
                                                 'name'    => 'char(100)',
                                                 'status'  => 'int(10)',
                                                 'allowed' => [
                                                               'moses',
                                                               'ingram',
                                                               'joice',
                                                              ]
                                                },
                            'host'           => 'mila',
                            'db'             => 'unknown',
                            'user'           => 'tom'
                           },
               'db'     => 'maxis',
               'server' => 'mc200',
               'user'   => 'hans'
              };

    If you have turned on -LowerCaseNames (see new()) then blocks as in the following example:

     <Dir>
      <AttriBUTES>
       Owner  root
      </attributes>
     </dir>

    would produce the following hash structure:

      $VAR1 = {
               'dir' => {
                         'attributes' => {
                                          'owner'  => "root",
                                         }
                        }
              };

    As you can see, the keys inside the config hash are normalized.

    Please note, that the above config block would result in a valid hash structure, even if
    -LowerCaseNames is not set! This is because *Config::General* does not use the block names to
    check if a block ends, instead it uses an internal state counter, which indicates a block end.

    If the module cannot find an end-block statement, then this block will be ignored.

NAMED BLOCKS
    If you need multiple blocks of the same name, then you have to name every block. This works much
    like Apache config. If the module finds a named block, it will create a hashref with the left
    part of the named block as the key containing one or more hashrefs with the right part of the
    block as key containing everything inside the block(which may again be nested!). As examples
    says more than words:

    # given the following sample <Directory /usr/frisco> Limit Deny Options ExecCgi Index
    </Directory> <Directory /usr/frik> Limit DenyAll Options None </Directory>

    # you will get:

      $VAR1 = {
               'Directory' => {
                               '/usr/frik' => {
                                               'Options' => 'None',
                                               'Limit' => 'DenyAll'
                                              },
                               '/usr/frisco' => {
                                                 'Options' => 'ExecCgi Index',
                                                 'Limit' => 'Deny'
                                                }
                              }
              };

    You cannot have more than one named block with the same name because it will be stored in a
    hashref and therefore be overwritten if a block occurs once more.

WHITESPACE IN BLOCKS
    The normal behavior of Config::General is to look for whitespace in block names to decide if
    it's a named block or just a simple block.

    Sometimes you may need blocknames which have whitespace in their names.

    With named blocks this is no problem, as the module only looks for the first whitespace:

     <person hugo gera>
     </person>

    would be parsed to:

      $VAR1 = {
               'person' => {
                            'hugo gera' => {
                                           },
                           }
              };

    The problem occurs, if you want to have a simple block containing whitespace:

     <hugo gera>
     </hugo gera>

    This would be parsed as a named block, which is not what you wanted. In this very case you may
    use quotation marks to indicate that it is not a named block:

     <"hugo gera">
     </"hugo gera">

    The save() method of the module inserts automatically quotation marks in such cases.

EXPLICIT EMPTY BLOCKS
    Beside the notation of blocks mentioned above it is possible to use explicit empty blocks.

    Normally you would write this in your config to define an empty block:

     <driver Apache>
     </driver>

    To save writing you can also write:

     <driver Apache/>

    which is the very same as above. This works for normal blocks and for named blocks.

IDENTICAL OPTIONS (ARRAYS)
    You may have more than one line of the same option with different values. Example:

     log  log1
     log  log2
     log  log2

    You will get a scalar if the option occurred only once or an array if it occurred more than
    once. If you expect multiple identical options, then you may need to check if an option occurred
    more than once:

      $allowed = $hash{jonas}->{tablestructure}->{allowed};
      if (ref($allowed) eq "ARRAY") {
        @ALLOWED = @{$allowed};
        else {
          @ALLOWED = ($allowed);
        }
      }

    The same applies to blocks and named blocks too (they are described in more detail below). For
    example, if you have the following config:

     <dir blah>
      user max
     </dir>
     <dir blah>
      user hannes
     </dir>

    then you would end up with a data structure like this:

      $VAR1 = {
               'dir' => {
                         'blah' => [
                                    {
                                     'user' => 'max'
                                    },
                                    {
                                     'user' => 'hannes'
                                    }
                                   ]
                        }
              };

    As you can see, the two identical blocks are stored in a hash which contains an
    array(-reference) of hashes.

    Under some rare conditions you might not want this behavior with blocks (and named blocks too).
    If you want to get one single hash with the contents of both identical blocks, then you need to
    turn the new() parameter -MergeDuplicateBlocks on (see above). The parsed structure of the
    example above would then look like this:

      $VAR1 = {
               'dir' => {
                         'blah' => {
                                    'user' => [
                                               'max',
                                               'hannes'
                                              ]
                                   }
                        }
              };

    As you can see, there is only one hash "dir->{blah}" containing multiple "user" entries. As you
    can also see, turning on -MergeDuplicateBlocks does not affect scalar options (i.e. "option =
    value"). In fact you can tune merging of duplicate blocks and options independent from each
    other.

    If you don't want to allow more than one identical options, you may turn it off by setting the
    flag *AllowMultiOptions* in the new() method to "no". If turned off, Config::General will
    complain about multiple occurring options with identical names!

  FORCE SINGLE VALUE ARRAYS
    You may also force a single config line to get parsed into an array by turning on the option
    -ForceArray and by surrounding the value of the config entry by []. Example:

     hostlist = [ foo.bar ]

    Will be a singlevalue array entry if the option is turned on. If you want it to remain to be an
    array you have to turn on -ForceArray during save too.

LONG LINES
    If you have a config value, which is too long and would take more than one line, you can break
    it into multiple lines by using the backslash character at the end of the line. The
    Config::General module will concatenate those lines to one single-value.

    Example:

     command = cat /var/log/secure/tripwire | \
     mail C<-s> "report from tripwire" \
     honey AT myotherhost.nl

    command will become: "cat /var/log/secure/tripwire | mail "-s" 'report from twire'
    honey AT myotherhost.nl"

HERE DOCUMENTS
    You can also define a config value as a so called "here-document". You must tell the module an
    identifier which indicates the end of a here document. An identifier must follow a "<<".

    Example:

     message <<EOF
      we want to
      remove the
      homedir of
      root.
     EOF

    Everything between the two "EOF" strings will be in the option *message*.

    There is a special feature which allows you to use indentation with here documents. You can have
    any amount of whitespace or tabulators in front of the end identifier. If the module finds
    spaces or tabs then it will remove exactly those amount of spaces from every line inside the
    here-document.

    Example:

     message <<EOF
        we want to
        remove the
        homedir of
        root.
        EOF

    After parsing, message will become:

     we want to
     remove the
     homedir of
     root.

    because there were the string " " in front of EOF, which were cut from every line inside the
    here-document.

INCLUDES
    You can include an external file at any position in your config file using the following
    statement in your config file:

     <<include externalconfig.rc>>

    If you turned on -UseApacheInclude (see new()), then you can also use the following statement to
    include an external file:

     include externalconfig.rc

    This file will be inserted at the position where it was found as if the contents of this file
    were directly at this position.

    You can also recursively include files, so an included file may include another one and so on.
    Beware that you do not recursively load the same file, you will end with an error message like
    "too many open files in system!".

    By default included files with a relative pathname will be opened from within the current
    working directory. Under some circumstances it maybe possible to open included files from the
    directory, where the configfile resides. You need to turn on the option -IncludeRelative (see
    new()) if you want that. An example:

     my $conf = Config::General(
      -ConfigFile => "/etc/crypt.d/server.cfg"
      -IncludeRelative => 1
     );

    /etc/crypt.d/server.cfg:

     <<include acl.cfg>>

    In this example Config::General will try to include *acl.cfg* from */etc/crypt.d*:

     /etc/crypt.d/acl.cfg

    The default behavior (if -IncludeRelative is not set!) will be to open just *acl.cfg*, wherever
    it is, i.e. if you did a chdir("/usr/local/etc"), then Config::General will include:

     /usr/local/etc/acl.cfg

    Include statements can be case insensitive (added in version 1.25).

    Include statements will be ignored within C-Comments and here-documents.

    By default, a config file will only be included the first time it is referenced. If you wish to
    include a file in multiple places, set /-IncludeAgain to true. But be warned: this may lead to
    infinite loops, so make sure, you're not including the same file from within itself!

    Example:

     # main.cfg
     <object billy>
      class=Some::Class
     <printers>
      include printers.cfg
     </printers>
     # ...
     </object>
      <object bob>
       class=Another::Class
      <printers>
      include printers.cfg
      </printers>
      # ...
     </object>

    Now "printers.cfg" will be include in both the "billy" and "bob" objects.

    You will have to be careful to not recursively include a file. Behaviour in this case is
    undefined.

COMMENTS
    A comment starts with the number sign #, there can be any number of spaces and/or tab stops in
    front of the #.

    A comment can also occur after a config statement. Example:

     username = max  # this is the comment

    If you want to comment out a large block you can use C-style comments. A /* signals the begin of
    a comment block and the */ signals the end of the comment block. Example:

     user  = max # valid option
     db    = tothemax
     /*
     user  = andors
     db    = toand
     */

    In this example the second options of user and db will be ignored. Please beware of the fact, if
    the Module finds a /* string which is the start of a comment block, but no matching end block,
    it will ignore the whole rest of the config file!

    NOTE: If you require the # character (number sign) to remain in the option value, then you can
    use a backslash in front of it, to escape it. Example:

     bgcolor = \#ffffcc

    In this example the value of $config{bgcolor} will be "#ffffcc", Config::General will not treat
    the number sign as the begin of a comment because of the leading backslash.

    Inside here-documents escaping of number signs is NOT required!

PARSER PLUGINS
    You can alter the behavior of the parser by supplying closures which will be called on certain
    hooks during config file processing and parsing.

    The general aproach works like this:

      sub ck {
        my($file, $base) = @_;
        print "_open() tries $file ... ";
        if ($file =~ /blah/) {
          print "ignored\n";
          return (0);
        } else {
          print "allowed\n";
          return (1, @_);
        }
      }

      my %c = ParseConfig(
                          -IncludeGlob      => 1,
                          -UseApacheInclude => 1,
                          -ConfigFile       => shift,
                          -Plug             => { pre_open => *ck }
                         );

    Output:

     _open() tries cfg ... allowed
     _open() tries x/*.conf ... allowed
     _open() tries x/1.conf ... allowed
     _open() tries x/2.conf ... allowed
     _open() tries x/blah.conf ... ignored

    As you can see, we wrote a little sub which takes a filename and a base directory as parameters.
    We tell Config::General via the Plug parameter of new() to call this sub everytime before it
    attempts to open a file.

    General processing continues as usual if the first value of the returned array is true. The
    second value of that array depends on the kind of hook being called.

    The following hooks are available so far:

    pre_open
        Takes two parameters: filename and basedirectory.

        Has to return an array consisting of 3 values:

         - 1 or 0 (continue processing or not)
         - filename
         - base directory

    pre_read
        Takes two parameters: the filehandle of the file to be read and an array containing the raw
        contents of said file.

        This hook will be applied in _read(). File contents are already available at this stage,
        comments will be removed, here-docs normalized and the like. This hook gets the unaltered,
        original contents.

        Has to return an array of 3 values:

         - 1 or 0 (continue processing or not)
         - the filehandle
         - an array of strings

        You can use this hook to apply your own normalizations or whatever.

        Be careful when returning the abort value (1st value of returned array 0), since in this
        case nothing else would be done on the contents. If it still contains comments or something,
        they will be parsed as legal config options.

    post_read
        Takes one parameter: a reference to an array containing the prepared config lines (after
        being processed by _read()).

        This hook will be applied in _read() when everything else has been done.

        Has to return an array of 2 values:

         - 1 or 0 (continue processing or not) [Ignored for post hooks]
         - a reference to an array containing the config lines

    pre_parse_value
        Takes 2 parameters: an option name and its value.

        This hook will be applied in _parse_value() before any processing.

        Has to return an array of 3 values:

         - 1 or 0 (continue processing or not)
         - option name
         - value of the option

    post_parse_value
        Almost identical to pre_parse_value, but will be applied after _parse_value() is finished
        and all usual processing and normalization is done.

    Not implemented yet: hooks for variable interpolation and block parsing.

OBJECT ORIENTED INTERFACE
    There is a way to access a parsed config the OO-way. Use the module Config::General::Extended,
    which is supplied with the Config::General distribution.

VARIABLE INTERPOLATION
    You can use variables inside your config files if you like. To do that you have to use the
    module Config::General::Interpolated, which is supplied with the Config::General distribution.

EXPORTED FUNCTIONS
    Config::General exports some functions too, which makes it somewhat easier to use it, if you
    like this.

    How to import the functions:

     use Config::General qw(ParseConfig SaveConfig SaveConfigString);

    ParseConfig()
        This function takes exactly all those parameters, which are allowed to the new() method of
        the standard interface.

        Example:

         use Config::General qw(ParseConfig);
         my %config = ParseConfig(-ConfigFile => "rcfile", -AutoTrue => 1);

    SaveConfig()
        This function requires two arguments, a filename and a reference to a hash structure.

        Example:

         use Config::General qw(SaveConfig);
         ..
         SaveConfig("rcfile", \%some_hash);

    SaveConfigString()
        This function requires a reference to a config hash as parameter. It generates a
        configuration based on this hash as the object-interface method save_string() does.

        Example:

         use Config::General qw(ParseConfig SaveConfigString);
         my %config = ParseConfig(-ConfigFile => "rcfile");
         .. # change %config something
         my $content = SaveConfigString(\%config);

CONFIGURATION AND ENVIRONMENT
    No environment variables will be used.

SEE ALSO
    I recommend you to read the following documents, which are supplied with Perl:

     perlreftut                     Perl references short introduction
     perlref                        Perl references, the rest of the story
     perldsc                        Perl data structures intro
     perllol                        Perl data structures: arrays of arrays

     Config::General::Extended      Object oriented interface to parsed configs
     Config::General::Interpolated  Allows one to use variables inside config files

LICENSE AND COPYRIGHT
    Copyright (c) 2000-2016 Thomas Linden

    This library is free software; you can redistribute it and/or modify it under the same terms as
    Perl itself.

BUGS AND LIMITATIONS
    See rt.cpan.org for current bugs, if any.

INCOMPATIBILITIES
    None known.

DIAGNOSTICS
    To debug Config::General use the Perl debugger, see perldebug.

DEPENDENCIES
    Config::General depends on the modules FileHandle, File::Spec::Functions, File::Glob, which all
    are shipped with Perl.

AUTHOR
    Thomas Linden <tlinden |AT| cpan.org>

VERSION
    2.63

Config::General(3pm)
NAME SYNOPSIS DESCRIPTION SUBROUTINES/METHODS
new() -ConfigFile -ConfigHash -String -AllowMultiOptions -LowerCaseNames -UseApacheInclude -IncludeRelative -IncludeDirectories -IncludeGlob -IncludeAgain -ConfigPath -MergeDuplicateBlocks -MergeDuplicateOptions -AutoLaunder -AutoTrue -FlagBits -DefaultConfig -Tie -InterPolateVars -InterPolateEnv -AllowSingleQuoteInterpolation -ExtendedAccess -StrictObjects -StrictVars -SplitPolicy -SplitDelimiter -StoreDelimiter -CComments -BackslashEscape -SlashIsDirectory -UseApacheIfDefine -Define -ApacheCompatible -UTF8 -SaveSorted -NoEscape -NormalizeBlock -NormalizeOption -NormalizeValue getall() files() save_file() save_string()
CONFIG FILE FORMAT BLOCKS NAMED BLOCKS WHITESPACE IN BLOCKS EXPLICIT EMPTY BLOCKS
array(-reference) of hashes.
LONG LINES HERE DOCUMENTS INCLUDES
new()) if you want that. An example:
COMMENTS PARSER PLUGINS OBJECT ORIENTED INTERFACE VARIABLE INTERPOLATION EXPORTED FUNCTIONS CONFIGURATION AND ENVIRONMENT SEE ALSO LICENSE AND COPYRIGHT BUGS AND LIMITATIONS INCOMPATIBILITIES DIAGNOSTICS DEPENDENCIES AUTHOR VERSION

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