Provided by: libgetdata-doc_0.11.0-6_all bug

NAME

       GetData - Perl bindings to the GetData library for Dirfile access

SYNOPSIS

         use GetData;

         my $DIRFILE = GetData::open("./dirfile/", $GetData::RDONLY);

         # the following calls are equivalent
         my $data = GetData::getdata($DIRFILE, "field", 5, 0, 1,
                                     $GetData::UINT8);
         my $data = $DIRFILE->getdata("field", 5, 0, 1, $GetData::UINT8);

DESCRIPTION

       This module provides simple, lightweight bindings from Perl to the C GetData library.  It
       provides a simple mapping between public C functions and Perl methods.  All C functions
       and constants are replicated in the GetData package.  These methods have the same name as
       their C counterparts, excluding the C namespace prefix `gd_' (or `GD_', for C preprocessor
       constants).

       The dirfile lvalue returned by GetData::open is a simplistic object.  Any GetData method
       which takes a dirfile as a parameter, may instead be called as method of the dirfile
       object itself.  (See the synopsis above for an example.)  Dirfile metadata entries (which
       are C structs of type gd_entry_t) are represented as simple hashes.

       By default, GetData does not export any symbols.  All symbols in the GetData package may
       be exported with:

         use GetData "all";

       but this is discouraged, as it will overwrite useful things like &CORE::open.

       Throughout the module, complex data are generally represented as "Math::Complex" objects,
       but may be simplified to ordinary floating point numbers if the imaginary part is zero.

CONSTANTS

       The module defines a large number of symbolic constants used by the API which mirror the
       constants defined in the C API.  The "constants" tag may be used to export just the
       constants from the module, if desired.  Some genericly useful sets of constants are
       discussed below.  Other constants are discussed in the method descriptions where they are
       used.

   Data Types
       GetData knows the following data types:

       $GetData::NULL
           the null data type, which returns no data.

       $GetData::UINT8
           unsigned 8-bit integer

       $GetData::INT8
           signed (two's complement) 8-bit integer

       $GetData::UINT16
           unsigned 16-bit integer

       $GetData::INT16
           signed (two's complement) 16-bit integer

       $GetData::UINT32
           unsigned 32-bit integer

       $GetData::INT32
           signed (two's complement) 32-bit integer

       $GetData::UINT64
           unsigned 64-bit integer

       $GetData::INT64
           signed (two's complement) 64-bit integer

       $GetData::FLOAT32
           IEEE-754 standard 32-bit single precision floating point number

       $GetData::FLOAT64
           IEEE-754 standard 64-bit double precision floating point number

       $GetData::COMPLEX64
           FORTRAN and C99 conformant 64-bit single precision floating point complex number

       $GetData::COMPLEX128
           FORTRAN and C99 conformant 128-bit double precision floating point complex number

   Encoding Types
       The following encoding types are known by GetData:

           $GetData::BZIP2_ENCODED, $GetData::FLAC_ENCODED, $GetData::GZIP_ENCODED,
           $GetData::LZMA_ENCODED, $GetData::SIE_ENCODED, $GetData::SLIM_ENCODED,
           $GetData::TEXT_ENCODED, $GetData::ZZIP_ENCODED, $GetData::ZZSLIM_ENCODED,
           $GetData::UNENCODED.

       Details of these encoding types are given in the dirfile-format(5) manual page.

   Entry Types
       The following symbols are used to indicate entry types:

           $GetData::NO_ENTRY, $GetData::BIT_ENTRY, $GetData::CARRAY_ENTRY,
           $GetData::CONST_ENTRY, $GetData::DIVIDE_ENTRY, $GetData::INDEX_ENTRY,
           $GetData::LINCOM_ENTRY, $GetData::LINTERP_ENTRY, $GetData::MPLEX_ENTRY,
           $GetData::MULTIPLY_ENTRY, $GetData::PHASE_ENTRY, $GetData::POLYNOM_ENTRY,
           $GetData::RAW_ENTRY, $GetData::RECIP_ENTRY, $GetData::SBIT_ENTRY,
           $GetData::STRING_ENTRY, $GetData::WINDOW_ENTRY

       Of these, $GetData::NO_ENTRY is used to flag invalid entry types and $GetData::INDEX_ENTRY
       is used only for the implicit INDEX field.  See gd_entry(3) and dirfile-format(5) for
       details of the other entry types.

   WINDOW Operators
       The following symbols are used to indicate WINDOW operators:

           $GetData::WINDOP_EQ, $GetData::WINDOP_GE, $GetData::WINDOP_GT, $GetData::WINDOP_LE,
           $GetData::WINDOP_LT, $GetData::WINDOP_NE, $GetData::WINDOP_CLR, $GetData::WINDOP_SET.

INPUT DATA

       Functions which take sets of data as input (add_carray, madd_carray, put_carray,
       put_carray_slice, and putdata) accept data in a number of ways.  The arguments specifying
       the data always appear at the end of the argument list.  They are represented as
       "{DATA...}" in the method descriptions below.  Input data arguments are parsed as follows.

       1.  If the first data argument is undef, then it is ignored and all subsequent arguments
           are taken as data:

               $dirfile->putdata("field_code", $first_frame, $first_sample,
                                 undef, @data)

           or

               $dirfile->putdata("field_code", $first_frame, $first_sample,
                                 undef, $data[0], $data[1], $data[2], ...)

       2.  Otherwise, if the first data argument is a reference to an array, the array is taken
           as data (and any further arguments are ignored):

               $dirfile->putdata("field_code", $first_frame, $first_sample,
                                 \@data)

       3.  Otherwise, if only two arguments make up the data argument list, and the second is a
           reference to an array, the first is taken as a type code specifing the conversion
           type, and the second is taken as the data:

               $dirfile->putdata("field_code", $first_frame, $first_sample,
                                 $GetData::UINT8, \@data)

       4.  Otherwise, if only two arguments make up the data argument list, and the second is not
           a reference to an array, the first is, again, taken as a type code, and the second is
           assumed to be a packed string containing the data in a format appropriate for the type
           code specified:

               $packed_data = pack("C", @data)
               $dirfile->putdata("field_code", $first_frame, $first_sample,
                                 $GetData::UINT8, $packed_data)

       5.  Otherwise, finally, the data argument list elements are simply taken as data
           themselves:

               $dirfile->putdata("field_code", $first_frame, $first_sample,
                                 @data)

           or

               $dirfile->putdata("field_code", $first_frame, $first_sample,
                                 $data[0], $data[1], $data[2], ...)

       GetData internally converts the Perl data into a format readable by the C API.  In cases 3
       and 4 above, the type the data is converted into is specified explicitly in the call.  In
       the other cases, GetData must guess an appropriate C type into which to convert the data.
       It does so by looking at the first data value:

       •   if the value is a "Math::Complex" object, the data are converted to double precision
           complex data ("COMPLEX128")

       •   if the value is an integer, the data are converted to a 64-bit signed integer
           ("INT64")

       •   otherwise, the data are converted to a double precision float ("FLOAT64").

       Of the above methods, the first is only necessary when the data array has only two
       elements, and so would be mistaken for method four if specified without the initial undef.
       Furthermore, the fourth method is typically the most efficient, since the packed data
       scalar can often be used as the input to the C API without need for type conversion.

ENTRY HASHES

       The replacement for the "gd_entry_t" object of the C API is a simple hash.  The key names
       are the same as the names of the "gd_entry_t" members.  (See gd_entry(3) for details).

       In entry hashes returned by GetData, only those keys appropriate for the entry type
       specified will be present.  Entry hashes passed to GetData from the caller may have other
       keys than those required by the entry type.  They will be ignored.

       The value associated with the "field_type" key will be one of the symbols listed under
       "Entry Types" above.  For entry types which have (potentially) more than one input field
       (DIVIDE, LINCOM, MPLEX, MULTIPLY, WINDOW), the value associated with the "in_fields" key
       will be a list of strings, regardless of how many elements it has; other entry types which
       provide "in_fields" will be a scalar, even though the key name is still plural.

       Elements of the "scalar" array which are undef indicate literal parameters (equivalent to
       "NULL" in the "gd_entry_t"'s "scalar" member).  Similarly, undef is used in "scalar_ind"
       where the C API uses -1, to indicate CONST fields, instead of CARRAYs.

NON-MEMBER FUNCTIONS

       encoding_support ($ENCODING)
           Returns $GetData::RDWR if the library can both read and write the specified encoding,
           $GetData::RDONLY if it can only read, or -1 otherwise.  $ENCODING should be one of the
           encoding symbols listed above in the "Encoding Types" section.

DIRFILE CREATION METHODS

       open ($DIRFILENAME, $FLAGS, $SEHANDLER=undef, $EXTRA=undef)
           Create or open a Dirfile database called $DIRFILENAME.  $FLAGS should be either
           $GetData::RDONLY (for read-only access) or $GetData::RDWR (for read-write access),
           optionally bitwise or'd with any of the following flags:

               $GetData::ARM_ENDIAN, $GetData::BIG_ENDIAN, $GetData::CREAT, $GetData::EXCL,
               $GetData::FORCE_ENCODING, $GetData::FORCE_ENDIAN, $GetData::IGNORE_DUPS,
               $GetData::IGNORE_REFS, $GetData::LITTLE_ENDIAN, $GetData::NOT_ARM_ENDIAN,
               $GetData::PEDANTIC, $GetData::PERMISSIVE, $GetData::PRETTY_PRINT, $GetData::TRUNC,
               $GetData::TRUNCSUB, $GetData::VERBOSE,

           and at most one of the encoding symbols listed above in the "Encoding Types" section
           or else $GetData::AUTO_ENCODED indicating that GetData should attempt to automatically
           determine the encoding.  The meaning of the dirfile flags may be found in the
           gd_cbopen(3) manual page.

           $SEHANDLER is a Perl callback function which will be executed whenever a syntax error
           is encountered.  It may be undef, if no callback is desired.  When called, $SEHANDLER
           will be passed two arguments.  The first is a reference to a hash containing the
           parser data.  The second is the $EXTRA scalar passed to this method.  $SEHANDLER is
           called in scalar context, and should return either:

           •   an integer, one of the symbolic constants:

                   $GetData::SYNTAX_ABORT, $GetData::SYNTAX_CONTINUE, $GetData::SYNTAX_IGNORE,
                   $GetData::SYNTAX_RESCAN;

               (see gd_cbopen(3) for their meaning), or

           •   a string containing the corrected line, in which case $GetData::SYNTAX_RESCAN is
               assumed; or,

           •   a reference to a list consisting of an integer, one of the "$GetData::SYNTAX_..."
               constants listed above, and then, optionally, a string containing the corrected
               line.

           This function always returns a Dirfile object, even if the call failed; the caller
           should use the returned dirfile's error() method to test for success.  On error, the
           returned object will be flagged as invalid.

       invalid_dirfile ()
           This function always returns a newly created, but invalid, Dirfile object.  Unlike an
           invalid dirfile created (either accidentally or purposefully) using open(), the
           dirfile returned by this function always has a zero error code.  See
           gd_invalid_dirfile(3).

DIRFILE OBJECT METHODS

       The following methods all operate on a dirfile object returned by one of the above methods
       and can either be called as:

         $GetData::method($dirfile, ...)

       or else, as

         $dirfile->method(...)

       without change in operation.

   List of Methods
       $dirfile->add_carray ($FIELD_NAME, $DATA_TYPE, $FRAGMENT_INDEX, {DATA...})
           Adds a new CARRAY field called $FIELD_NAME to the metadata fragment indexed by
           $FRAGMENT_INDEX.  The storage type of the CARRAY is given by $DATA_TYPE, which should
           be one of the symbols listed above under "Data Types".  The value of the CARRAY is
           then set to the data given in the "{DATA...}" argument list, which also determines its
           length.  See the "Input Data" section above for details on the allowed forms of
           "{DATA...}".  See gd_add_carray(3).

       $dirfile->add_const ($FIELD_NAME, $DATA_TYPE, [$VALUE, $FRAGMENT_INDEX])
           Adds a new CONST field called $FIELD_NAME to the metadata fragment indexed by
           $FRAGMENT_INDEX, or to the primary format file if omitted.  The $DATA_TYPE argument
           indicates the storage type, which should be one of the symbols listed above under
           "Data Types".  If given, the value of the field is set to $VALUE, otherwise the field
           will be initialised to zero.  See gd_add_const(3).

       $dirfile->aliases ($FIELD_CODE)
           In scalar context, returns the number of aliases of $FIELD_CODE.  In list context,
           returns an array of alias names for $FIELD_CODE.  See gd_naliases(3) and
           gd_aliases(3).

       $dirfile->carrays ($RETURN_TYPE)
           Returns the value of all carrays (excluding metafields) in the dirfile after
           converting them to the return type $RETURN_TYPE, which should be one of the symbols
           listed under "Data Types" above.  If called in scalar context, returns a reference to
           an array of packed string data.  If called in list context, returns an array of arrays
           of unpacked data.  See gd_carrays(3).

       $dirfile->close ()
           Closes the dirfile, writing changes to disk.  Upon successful completion, the dirfile
           object will be invalidated, prohibiting further operation on it.  A dirfile which is
           destroyed by garbage collection is discarded (see "discard" below).  This function
           should be called if metadata need to be written to disk before the object goes out of
           scope.  See gd_close(3).

       $dirfile->constants ($RETURN_TYPE)
           Returns the value of all constants (excluding metafields) in the dirfile after
           converting them to the return type $RETURN_TYPE, which should be one of the symbols
           listed under "Data Types" above.  If called in scalar context, returns a packed string
           containing the data.  If called in list context, the data will be unpacked and
           returned as an array.  See gd_constants(3).

       $dirfile->discard ()
           Closes the dirfile, ignoring changes to metadata, but writing changed data to disk.
           Upon successful completion, the dirfile object will be invalidated, prohibiting
           further operation on it.  This function is called automatically by the dirfile
           destructor, and need not be called explicitly.  To save the metadata on close, use
           "close".  See gd_discard(3).

       $dirfile->entry ($FIELD_CODE)
           If called in scalar context, returns the entry type of $FIELD_CODE, one of the symbols
           listed above under "Entry Types".  In array context, returns a hash describing the
           indicated field.  See gd_entry_type(3) and gd_entry(3).

       $dirfile->match_entries ($REGEX, $FRAGMENT, $TYPE, $FLAGS)
           In scalar context, returns the number of entries matching the supplied criteria.  In
           list context, returns an array of the names of the entries.  If $REGEX is not undef,
           it is a regular expression which is matched against entry names.

           NB: The regular expression handling is done in the underlying C library, not in Perl.
           As a result, using Perl's regex grammar in $REGEX usually won't work as desired.  If
           the C GetData library has Perl-Compatible Regular Expression (PCRE) support, the
           $GetData::REGEX_PCRE flag can be used to select a regular expression grammar which is
           very similar to Perl's own.

           If $FRAGMENT is not $GetData::ALL_FRAGMENTS or undef, only entries defined in the
           specified fragment are searched.  If $TYPE is one of the entry types listed above
           under "Entry Types", only entries of that type are considered.  Alternatley, $TYPE may
           be one of:

               $GetData::ALL_ENTRIES, $GetData::SCALAR_ENTRIES, $GetData::VECTOR_ENTRIES.

           Setting $TYPE to undef is equivalent to setting it to $GetData::ALL_ENTRIES.  If not
           undef, which is treated as zero, $FLAGS should be zero or more of the following flags:

               $GetData::ENTRIES_HIDDEN, $GetData::ENTRIES_NOALIAS, $GetData::REGEX_PCRE,
               $GetData::REGEX_EXTENDED, $GetData::REGEX_ICASE, $GetData::REGEX_CASELESS,
               $GetData::REGEX_JAVASCRIPT, $GetData::REGEX_UNICODE

           See gd_match_entries(3) for the meaning of these symbols.

       $dirfile->entry_list ($PARENT, $TYPE, $FLAGS)
           In scalar context, returns the number of entries matching the supplied criteria.  In
           list context, returns an array of the names of the entries.  If $PARENT is undef, top-
           level entries are considered, otherwise meta entries under $PARENT are considered.
           For $TYPE and $FLAGS, see "$dirfile-"match_entries> above (the regex flags listed
           there are ignored by this function), and also gd_nentries(3) and gd_entry_list(3).

       $dirfile->error ()
           Returns the error code of the last operation on this dirfile.  See gd_error(3).

       $dirfile->error_string ()
           Returns a string describing the error encountered (if any) by the last operation on
           this dirfile.  See gd_error_string(3).

       $dirfile->field_list ()
           Equivalent to: "$dirfile->entry_list(undef, undef, undef)".

       $dirfile->field_list_by_type ($TYPE)
           Equivalent to: "$dirfile->entry_list(undef, $TYPE, undef)".

       $dirfile->fragment_affixes ($FRAGMENT_INDEX)
           Returns an array containing the prefix (first) and suffix (second) of the fragment
           indexed by $FRAGMENT_INDEX.  See gd_fragment_affixes(3).

       $dirfile->fragments ()
           In scalar context, returns the number of metadata fragments in the dirfile.  In list
           context, returns an array of pathnames to the fragments on disk, in the order that
           they're indexed.  See gd_nfragments(3) and gd_fragmentname(3).

       $dirfile->get_carray ($FIELD_CODE, $RETURN_TYPE)
           Returns the value of the CARRAY named $FIELD_CODE after converting its elements to the
           return type $RETURN_TYPE, which should be one of the symbols listed under "Data Types"
           above.  If $RETURN_TYPE is $GetData::NULL, in scalar context this function returns
           undef.  Otherwise, if called in scalar context, returns a packed string containing the
           data.  If called in list context, the data will be unpacked and returned as an array.
           See gd_get_carray(3).

       $dirfile->get_carray_slice ($FIELD_CODE, $START, $LEN, $RETURN_TYPE)
           Returns the value of a portion of the CARRAY named $FIELD_CODE after converting its
           elements to the return type $RETURN_TYPE, which should be one of the symbols listed
           under "Data Types" above.  The first element returned is given by $START, and the
           number of elements by $LEN.  If $RETURN_TYPE is $GetData::NULL, in scalar context this
           function returns undef.  Otherwise, if called in scalar context, returns a packed
           string containing the data.  If called in list context, the data will be unpacked and
           returned as an array.  Less data than requested may be returned, if insufficient data
           exist.  See gd_get_carray_slice(3).

       $dirfile->get_constant ($FIELD_CODE, $RETURN_TYPE)
           Returns the value of the CONST named $FIELD_CODE after converting it to the return
           type $RETURN_TYPE, which should be one of the symbols listed under "Data Types" above.
           If $RETURN_TYPE is $GetData::NULL, returns undef on success.  See gd_get_constant(3).

       $dirfile->getdata ($FIELD_CODE, $FIRST_FRAME, $FIRST_SAMP, $NUM_FRAMES, $NUM_SAMP,
       $RETURN_TYPE)
           Returns data from the field specified by $FIELD_CODE after converting them to the
           return type $RETURN_TYPE, which should be one of the symbols listed under "Data Types"
           above.  The first sample returned is $FIRST_SAMP samples after the start of
           $FIRST_FRAME and the amount of data returned is $NUM_FRAMES frames plus $NUM_SAMP
           samples.  If $RETURN_TYPE is $GetData::NULL, in scalar context this function returns
           the number of samples read.  Otherwise, if called in scalar context, it returns a
           string of packed data.  If called in array context, the data will be unpacked and
           returned as an array.  Complex data are returned as "Math::Complex" objects.  See
           gd_getdata(3).

       $dirfile->get_string ($FIELD_CODE)
           Returns the value of the STRING named $FIELD_CODE.  See gd_get_string(3).

       $dirfile->include ($FILE, $PARENT_FRAGMENT, $FLAGS, [$PREFIX, $SUFFIX])
           Includes the fragment metadata file $FILE under the fragment indexed by
           $PARENT_FRAGMENT.  $FLAGS should be a bitwise or'd collection of zero or more of the
           following flags:

               $GetData::BIG_ENDIAN, $GetData::CREAT, $GetData::EXCL, $GetData::FORCE_ENCODING,
               $GetData::FORCE_ENDIAN, $GetData::IGNORE_DUPS, $GetData::IGNORE_REFS,
               $GetData::LITTLE_ENDIAN, $GetData::PEDANTIC, $GetData::TRUNC,

           and at most one of the encoding symbols listed above in the "Encoding Types" section
           or else $GetData::AUTO_ENCODED indicating that GetData should attempt to automatically
           determine the encoding.  If $PREFIX or $SUFFIX are omitted or undef, the added
           fragment will contain no such affix.  See gd_include_affix(3).

       $dirfile->madd_carray ($PARENT, $FIELD_NAME, $DATA_TYPE, {DATA...})
           Adds a new CARRAY metafield called $FIELD_NAME under the parent field $PARENT.  The
           storage type of the CARRAY is given by $DATA_TYPE, which should be one of the symbols
           listed above under "Data Types".  The value of the CARRAY is then set to the data
           given in the "{DATA...}" argument list, which also determines its length.  See the
           "Input Data" section above for details on the allowed forms of "{DATA...}".  See
           gd_madd_carray(3).

       $dirfile->madd_const ($PARENT, $FIELD_NAME, $DATA_TYPE, [$VALUE])
           Adds a new CONST metafield called $FIELD_NAME under the field $PARENT.  The $DATA_TYPE
           argument indicates the storage type, which should be one of the symbols listed above
           under "Data Types".  If given, the value of the field is set to $VALUE, otherwise the
           field will be initialised to zero.  See gd_madd_const(3).

       $dirfile->mcarrays ($PARENT, $RETURN_TYPE)
           Behaves analogously to carrays() (q.v.), but returns CARRAYs which are metafields
           under the parent specified by $PARENT.

       $dirfile->mconstants ($PARENT, $RETURN_TYPE)
           Behaves analogously to constants() (q.v.), but returns CONSTs which are metafields
           under the parent specified by $PARENT.

       $dirfile->mfield_list ($PARENT)
           Equivalent to "$dirfile->entry_list($PARENT, undef, undef)".

       $dirfile->mfield_list_by_type ($PARENT, $TYPE)
           Equivalent to "$dirfile->entry_list($PARENT, $TYPE, undef)".

       $dirfile->mstrings ($PARENT)
           Behaves analogously to strings() (q.v.), but returns STRINGs which are metafields
           under the parent specified by $PARENT.

       $dirfile->mvector_list ($PARENT)
           Equivalent to:
             $dirfile->entry_list($PARENT, $GetData::VECTOR_ENTRIES, undef).

       $dirfile->parser_callback ($SEHANDLER, $EXTRA=undef)
           Sets the registered parser callback function for the dirfile to $SEHANDLER, or to
           nothing if undef, and updates the $EXTRA parameter.  See gd_parser_callback(3).

       $dirfile->put_carray ($FIELD_CODE, {DATA...})
           Sets the value of the CARRAY named $FIELD_CODE to the values contained in the
           "{DATA...}" argument list.  See the "Input Data" section above for details on the
           allowed forms of "{DATA...}".  See gd_put_carray(3).

       $dirfile->put_carray_slice ($FIELD_CODE, $START, {DATA...})
           Sets a value of the portion of the CARRAY named $FIELD_CODE beginning with element
           numbered $START to the values contained in the "{DATA...}" argument list.  See the
           "Input Data" section above for details on the allowed forms of "{DATA...}".  See
           gd_put_carray_slice(3).

       $dirfile->put_constant ($FIELD_CODE, $DATUM)
           Sets the value of the CONST field $FIELD_CODE to the value $DATUM.  See
           gd_put_constant(3).

       $dirfile->putdata ($FIELD_CODE, $FIRST_FRAME, $FIRST_SAMPLE, {DATA...})
           Sets a portion of the vector given by $FIELD_CODE to the values contained in the
           "{DATA...}" argument list.  The first sample written is $FIRST_SAMPLE samples after
           the start of $FIRST_FRAME.  See the "Input Data" section above for details on the
           allowed forms of "{DATA...}".  See gd_putdata(3).

       $dirfile->strings ()
           In scalar context, returns the number of STRING fields.  In list context, returns an
           array of strings containing the values of all the STRING fields.  See gd_strings(3).

       $dirfile->strtok ($STRING)
           Tokenises $STRING, returning an array of tokens.  See gd_strtok(3).

       $dirfile->vector_list ()
           Equivalent to:
             $dirfile->entry_list(undef, $GetData::VECTOR_ENTRIES, undef).

   Other Methods
       For the most part, following methods behave identically to their C API counterpart.  See
       the corresponding C API manual page for details.  Different behaviour, if any, is
       indicated.

       $dirfile->add ($ENTRY)
           $ENTRY should be a reference to an entry hash; see "ENTRY HASHES" above.

       $dirfile->add_alias ($FIELD_CODE, $TARGET, [$FRAGMENT_INDEX])
           $FRAGMENT_INDEX = 0 is assumed if not specified.

       $dirfile->add_bit ($FIELD_CODE, $IN_FIELD, $BITNUM, $NUMBITS, [$FRAGMENT_INDEX])
           $FRAGMENT_INDEX = 0 is assumed if not specified.

       $dirfile->add_divide ($FIELD_CODE, $IN_FIELD1, $IN_FIELD2, [$FRAGMENT_INDEX])
           $FRAGMENT_INDEX = 0 is assumed if not specified.

       $dirfile->add_lincom ($FIELD_CODE, $N_FIELDS, $IN_FIELDS, $M, $B, [$FRAGMENT_INDEX])
           $IN_FIELDS, $M, and $B should be references to arrays of the appropriate length.  The
           elements of $M and $B may be of any numerical type, including "Math::Complex".
           $FRAGMENT_INDEX = 0 is assumed if not specified.

       $dirfile->add_linterp ($FIELD_CODE, $IN_FIELD, $TABLE, [$FRAGMENT_INDEX])
           $FRAGMENT_INDEX = 0 is assumed if not specified.

       $dirfile->add_mplex ($FIELD_CODE, $IN_FIELD, $COUNT_FIELD, $COUNT_VAL, $COUNT_MAX,
       [$FRAGMENT_INDEX])
           $FRAGMENT_INDEX = 0 is assumed if not specified.

       $dirfile->add_multiply ($FIELD_CODE, $IN_FIELD1, $IN_FIELD2, [$FRAGMENT_INDEX])
           $FRAGMENT_INDEX = 0 is assumed if not specified.

       $dirfile->add_phase ($FIELD_CODE, $IN_FIELD, $SHIFT, [$FRAGMENT_INDEX])
           $FRAGMENT_INDEX = 0 is assumed if not specified.

       $dirfile->add_polynom ($FIELD_CODE, $POLY_ORD, $IN_FIELD, $A, [$FRAGMENT_INDEX])
           $A should be a reference to an array of numbers (of any numerical type, including
           "Math::Complex") of the appropriate length.  $FRAGMENT_INDEX = 0 is assumed if not
           specified.

       $dirfile->add_raw ($FIELD_CODE, $DATA_TYPE, $SPF, [$FRAGMENT_INDEX])
           $DATA_TYPE should be one of the symbols listed under "Data Types" above.
           $FRAGMENT_INDEX = 0 is assumed if not specified.

       $dirfile->add_recip ($FIELD_CODE, $IN_FIELD, $DIVIDEND, [$FRAGMENT_INDEX])
           $DIVIDEND may be of any numerical type, including "Math::Complex".  $FRAGMENT_INDEX =
           0 is assumed if not specified.

       $dirfile->add_sbit ($FIELD_CODE, $IN_FIELD, $BITNUM, $NUMBITS, [$FRAGMENT_INDEX])
           $FRAGMENT_INDEX = 0 is assumed if not specified.

       $dirfile->add_spec ($LINE, [$FRAGMENT_INDEX])
           $FRAGMENT_INDEX = 0 is assumed if not specified.

       $dirfile->add_string ($FIELD_CODE, $VALUE, [$FRAGMENT_INDEX])
           $FRAGMENT_INDEX = 0 is assumed if not specified.

       $dirfile->add_window ($FIELD_CODE, $IN_FIELD, $CHECK_FIELD, $WINDOP, $THRESHOLD,
       [$FRAGMENT_INDEX])
           $WINDOP should be one of the symbols listed under "WINDOW Operators" above.
           $FRAGMENT_INDEX = 0 is assumed if not specified.

       $dirfile->alias_target ($FIELD_CODE)

       $dirfile->alter_affixes ($FRAGMENT_INDEX, $PREFIX, [$SUFFIX])
           If $PREFIX or $SUFFIX are undef, or if $SUFFIX is omitted, that affix is not changed.

       $dirfile->alter_bit ($FIELD_CODE, [$IN_FIELD, $BITNUM, $NUMBITS])
           Arguments not given or set to undef are not changed.  Additionally, if "$BITNUM ==
           -1", or "$NUMBITS == 0", that parameter is not changed.

       $dirfile->alter_carray ($FIELD_CODE, $CONST_TYPE, $ARRAY_LEN)
           $CONST_TYPE should be one of the symbols listed under "Data Types" above.

       $dirfile->alter_const ($FIELD_CODE, [$CONST_TYPE])
           If $CONST_TYPE is omitted, or equal to $GetData::NULL, it is not changed; otherwise,
           it should be one of the symbols listed under "Data Types" above.

       $dirfile->alter_divide ($FIELD_CODE, [$IN_FIELD1, $IN_FIELD2])
           Arguments not given or set to undef are not changed.

       $dirfile->alter_encoding ($ENCODING, [$FRAGMENT_INDEX, $RECODE])
           Both $FRAGMENT_INDEX and $RECODE default to 0 if not given.

       $dirfile->alter_endianness ($BYTE_SEX, [$FRAGMENT_INDEX, $RECODE])
           Both $FRAGMENT_INDEX and $RECODE default to 0 if not given.

       $dirfile->alter_entry ($FIELD_CODE, $ENTRY, [$RECODE])
           $ENTRY should be a reference to an entry hash; see "ENTRY HASHES" above.  If not
           given, $RECODE defaults to 0.

       $dirfile->alter_frameoffset ($OFFSET, [$FRAGMENT_INDEX, $RECODE])
           Both $FRAGMENT_INDEX and $RECODE default to 0 if not given.

       $dirfile->alter_lincom ($FIELD_CODE, [$N_FIELDS, $IN_FIELDS, $M, $B])
           Arguments not given or set to undef are not changed.  If given, $IN_FIELDS, $M, and $B
           should be references to arrays of the appropriate length.

       $dirfile->alter_linterp ($FIELD_CODE, [$IN_FIELD, $TABLE, $RENAME_TABLE])
           Arguments not given or set to undef are not changed.  If not given, $RENAME_TABLE
           defaults to 0.

       $dirfile->alter_mplex ($FIELD_CODE, [$IN_FIELD, $COUNT_FIELD, $COUNT_VAL, $COUNT_MAX])
           Arguments not given or set to undef are not changed.  Additionally, if $COUNT_VAL or
           $COUNT_MAX are -1, that parameter is not chaged.

       $dirfile->alter_multiply ($FIELD_CODE, [$IN_FIELD1, $IN_FIELD2])
           Arguments not given or set to undef are not changed.

       $dirfile->alter_phase ($FIELD_CODE, $IN_FIELD, $SHIFT)
           If "$IN_FIELD == undef", it is not changed.

       $dirfile->alter_polynom ($FIELD_CODE, [$POLY_ORD, $IN_FIELD, $A])
           Arguments not given or set to undef are not changed.  Additionally, if "$POLY_ORD ==
           0", it is not changed.

       $dirfile->alter_protection ($PROTECTION_LEVEL, $FRAGMENT_INDEX)

       $dirfile->alter_raw ($FIELD_CODE, [$DATA_TYPE, $SPF, $RECODE])
           Arguments not given or set to undef are not changed.  Additionally, if "$DATA_TYPE ==
           $GetData::NULL" or "$SPF == 0", that parameter is not changed.  If not given, $RECODE
           defaults to 0.

       $dirfile->alter_recip ($FIELD_CODE, [$IN_FIELD, $DIVIDEND])
           Arguments not given or set to undef are not changed.  Additionally, if "$DIVIDEND ==
           0", it is not changed.  $DIVIDEND may be of any numerical type, including
           "Math::Complex".

       $dirfile->alter_sbit ($FIELD_CODE, [$IN_FIELD, $BITNUM, $NUMBITS])
           Arguments not given or set to undef are not changed.  Additionally, if "$BITNUM ==
           -1", or "$NUMBITS == 0", that parameter is not changed.

       $dirfile->alter_spec ($LINE, [$RECODE])
           If not given, $RECODE defaults to 0.

       $dirfile->alter_window ($FIELD_CODE, $IN_FIELD, $CHECK_FIELD, $WINDOP, $THRESHOLD)
           If $IN_FIELD or $CHECK_FIELD are undef, or if "$WINDOP == $GetData::WINDOP_UNK", that
           paremeter is not changed. Otherwise, $WINDOP should be one of the symbols listed under
           "WINDOW Operators" above.

       $dirfile->array_len ($FIELD_CODE)

       $dirfile->bof ($FIELD_CODE)

       $dirfile->delete ($FIELD_CODE, [$FLAGS])
           If not given, $FLAGS defaults to 0.  Otherwise, it should be a bitwise or'd collection
           of zero or more of the following flags:

               $GetData::DEL_DATA, $GetData::DEL_DEREF, $GetData::DEL_FORCE, $GetData::DEL_META.

       $dirfile->desync ([$FLAGS])
           If omitted, $FLAGS defaults to zero.  Otherwise, it should be zero or more of the
           following flags bitwise or'd together:

               $GetData::DESYNC_PATHCHECK, $GetData::DESYNC_REOPEN.

       $dirfile->dirfilename ()

       $dirfile->dirfile_standards ([$VERSION])
           In addition to a simple integer verison number, $VERSION may be one of the symbols

               $GetData::VERSION_CURRENT, $GetData::VERSION_EARLIEST, $GetData::VERSION_LATEST.

           If not given, $GetData::VERSION_CURRENT is assumed.

       $dirfile->encoding ($FRAGMENT_INDEX)

       $dirfile->endianness ($FRAGMENT_INDEX)

       $dirfile->eof ($FIELD_CODE)

       $dirfile->error_count ()

       $dirfile->flags ([$SET, $RESET])
           If omitted, $SET and $RESET default to 0.  Otherwise, they should be zero or more of
           the following flags, bitwise or'd together:

               $GetData::PRETTY_PRINT, $GetData::VERBOSE.

       $dirfile->flush ($FIELD_CODE)

       $dirfile->fragment_index ($FIELD_CODE)

       $dirfile->fragmentname ($FRAGMENT_INDEX)

       $dirfile->frameoffset ($FRAGMENT_INDEX)

       $dirfile->framenum ($FIELD_CODE, $VALUE, [$START, $END])
           $START and $END default to 0 if not given.

       $dirfile->hidden ($FIELD_CODE)

       $dirfile->hide ($FIELD_CODE)

       $dirfile->madd ($ENTRY, $PARENT)
           $ENTRY should be a reference to an entry hash; see "ENTRY HASHES" above.

       $dirfile->madd_alias ($PARENT, $FIELD_CODE, $TARGET)

       $dirfile->madd_bit ($PARENT, $FIELD_CODE, $IN_FIELD, $BITNUM, $NUMBITS)

       $dirfile->madd_divide ($PARENT, $FIELD_CODE, $IN_FIELD1, $IN_FIELD2)

       $dirfile->madd_lincom ($PARENT, $FIELD_CODE, $N_FIELDS, $IN_FIELDS, $M, $B)
           $IN_FIELDS, $M, and $B should be references to arrays of the appropriate length.  The
           elements of $M and $B may be of any numerical type, including "Math::Complex".

       $dirfile->madd_linterp ($PARENT, $FIELD_CODE, $IN_FIELD, $TABLE)

       $dirfile->madd_mplex ($PARENT, $FIELD_CODE, $IN_FIELD, $COUNT_FIELD, $COUNT_VAL,
       $COUNT_MAX)

       $dirfile->madd_multiply ($PARENT, $FIELD_CODE, $IN_FIELD1, $IN_FIELD2)

       $dirfile->madd_phase ($PARENT, $FIELD_CODE, $IN_FIELD, $SHIFT)

       $dirfile->madd_polynom ($PARENT, $FIELD_CODE, $POLY_ORD, $IN_FIELD, $A)
           $A should be a reference to an array of numbers (of any numerical type, including
           "Math::Complex") of the appropriate length.

       $dirfile->madd_recip ($PARENT, $FIELD_CODE, $IN_FIELD, $DIVIDEND)
           $DIVIDEND may be of any numerical type, including "Math::Complex".

       $dirfile->madd_sbit ($PARENT, $FIELD_CODE, $IN_FIELD, $BITNUM, $NUMBITS)

       $dirfile->madd_spec ($LINE, $PARENT)

       $dirfile->madd_string ($PARENT, $FIELD_CODE, $VALUE)

       $dirfile->madd_window ($PARENT, $FIELD_CODE, $IN_FIELD, $CHECK_FIELD, $WINDOP, $THRESHOLD)
           $WINDOP should be one of the symbols listed under "WINDOW Operators" above.

       $dirfile->malter_spec ($LINE, $PARENT, [$RECODE])
           If not given, $RECODE defaults to 0.

       $dirfile->metaflush ()

       $dirfile->move ($FIELD_CODE, $NEW_FRAGMENT, [$MOVE_DATA])
           If not given, $FLAGS defaults to 0.  Otherwise, it should be a bitwise or'd collection
           of zero or more of the following flags:

               $GetData::REN_DANGLE, $GetData::REN_DATA, $GetData::REN_FORCE, $GetData::REN_UPDB.

       $dirfile->mplex_lookback ($LOOKBACK)

       $dirfile->native_type ($FIELD_CODE)
           The returned value will be one of the symbols listed above under "Data Types".

       $dirfile->nframes ()

       $dirfile->parent_fragment ($FRAGMENT_INDEX)

       $dirfile->protection ($FRAGMENT_INDEX)

       $dirfile->put_string ($FIELD_CODE, $STRING)

       $dirfile->raw_close ($FIELD_CODE)

       $dirfile->raw_filename ($FIELD_CODE)

       $dirfile->reference ([$FIELD_CODE])
           If $FIELD_CODE is not given or undef, this function simply reports the current
           reference field.

       $dirfile->rename ($OLD_CODE, $NEW_NAME, [$FLAGS])
           If not given, $FLAGS defaults to 0.  Otherwise, it should be a bitwise or'd collection
           of zero or more of the following flags:

               $GetData::REN_DANGLE, $GetData::REN_DATA, $GetData::REN_FORCE, $GetData::REN_UPDB.

       $dirfile->rewrite_fragment ($FRAGMENT_INDEX)

       $dirfile->seek ($FIELD_CODE, $FRAME_NUM, $SAMPLE_NUM, [$FLAGS])
           If not given, $FLAGS defaults to $GetData::SEEK_SET.  Otherwise, it should be one of:

               $GetData::SEEK_CUR, $GetData::SEEK_END, $GetData::SEEK_SET.

           Furthermore, this value should be bitwise or'd with $GetData::SEEK_WRITE if the next
           operation on the field is a write (via "putdata").

       $dirfile->spf ($FIELD_CODE)

       $dirfile->sync ($FIELD_CODE)

       $dirfile->tell ($FIELD_CODE)

       $dirfile->unhide ($FIELD_CODE)

       $dirfile->uninclude ($FRAGMENT_INDEX, [$DEL])
           If not given, $DEL defaults to 0.

       $dirfile->validate ($FIELD_CODE)

       $dirfile->verbose_prefix ([$PREFIX])
           If $PREFIX is omitted or undef, the prefix is removed.

COPYRIGHT

       Copyright (C) 2012-2015 D. V. Wiebe

       GetData is free software; you can redistribute it and/or modify it under the terms of the
       GNU Lesser General Public License as published by the Free Software Foundation: either
       version 2.1 of the License, or (at your option) any later version.

       GetData is distributed in the hope that it will be useful, but without any warranty;
       without even the implied warranty of merchantability or fitness for a particular purpose.
       See the GNU Lesser General Public License for more details.

SEE ALSO

       Math::Complex(3), dirfile(5)