ABOUT iotk

The input/output tool kit (IOTK) is a Fortran90 library intended to provide a simplified access to tagged files formatted using some specific rule. A tagged file is a file containing tags and data, and can be textual, in which case a XML-compliant format is used, or binary, in which case a special format is used. The structure of the obtained files is hierarchical and suitable to represent complex objects. Textual files can be accessed with an XML browser or read with an XML parser.

IOTK has a simple Fortran interface, some-what similar to the interface of the native Fortran i/o library. The library interface is overloaded over all Fortran types, kinds and ranks, so that the same interface is used to write a scalar integer or a matrix of double precision real numbers. Moreover, when reading binary files, kind conversion (e.g. from single to double precision) is performed transparently by the library.

Even if the way used by IOTK to store the tags in binary files is not standard, there is a one-to-one correspondence between binary files and textual files, so that it is possible to transform a (fast but unportable) binary file into a (portable and human-readable) XML file without any knowledge about its content. A small external tool to perform these conversions is provided with this package.

Refer to the documentation in the package for a complete reference.

Note that this kit is not conceived an XML parser, but it can be used as a writer/parser for a limited subset of XML language.

Current limitations:
• DTD informations are not processed.
• There is presently no feature to list the tags in a file, or the
attributes in a tag. To found a tag or an attribute, its name has to be known.
• Access to files is serial. If data are written in a given order and read in a different order, performance overheads are expected. This problem can be partially overcome by splitting the file in a number of smaller files and pointing to them with virtual links (see the documentation for details).