FETE(A front end text editor)

Abstract

The front-end processing for text processing with syntax validation is proposed. As is known, the text processing may slow down dramatically at the peak time, and the software editor is becoming a significant overhead in a computing system. The complexity of the syntax directed editor would be greatly decreased by employing front-end processing, so that hardware text editor becomes feasible with the reduced complexity. This environment differs from the existing software programming environments by the following characteristics; it supports interactive textual viewpoint, reduces the complexity of syntax directed editor, increases the portability, it has the multi-lingual characteristics, and it supports multi-user in time sharing system at the low cost. This thesis also proposes an efficient architecture, called FETE, of a hardware text editor and system organization. The text editor is partitioned into 3 independent processors. This system architecture supports the parallelism and reduces the design complexities. The implementation of FETE is emulated on VAX 11/780 running under UNIX operating system. It shows that primitive operations of the screen editing reguire 4K bytes of control storage. The memory requirement for monitor program is less than 8K bytes. Of course, the requirement of memory certainly increases with the extension of functions but the emulation result shows that, on the average, 140 bytes of memory is needed for each text processing function. It represents that the hardware processor performs the text editing function without significant cost while validating the syntax of program.