### Overview

This command line interface is an implementation of the FLAM algorithms and access method up to version 4. Its purpose is to compress and decompress files in a format that allows easy exchange of data with numerous computer types from a wide range of manufacturers. Moreover, it offers character conversion and the option of encrypting compressed or uncompressed data.

Its heterogeneous compatibility also renders FLAM particularly suitable for long-term archiving of data, since the reproducibility of this data is no longer tied to the life cycle of a specific system. In addition, FLAM enables files to be converted in almost any way, i.e. to files with a different organization, a different record format or a different character set.

The architecture of the software is layer-oriented, i.e. it is made up of a series of hierarchically arranged functional groups which are completely distinct from one another and which communicate via defined interfaces. Since these interfaces are open, it is up to the user to choose the extent to which he wishes FLAM to be integrated in his applications.

FLAM can be invoked either by means of a command or by an application program via the corresponding interface. Although FLAM is capable of compressing any type of file, it was originally designed for files with a largely standardized record structure and character-coded data. It is most efficient at compressing such files. The above requirements are normally satisfied if the processing application programs are written in a high-level programming language. This chapter attempts to assist the user in deciding when, and if so how, FLAM can be used effectively and with the optimum benefit.

The flam command may contain the necessary information either in the form of parameters in the command line itself or as FLAM parameters in a parameter file, which is referred to by the parameter parfile=parameter file. The FLAM command is described in a own chapter below and discusses these parameters in greater detail. Unless otherwise explicitly mentioned, all the information in this chapter relating to the use of parameters in the command line applies equally to the parameters in the parameter file.