VAX-11 Text Editing Reference Manual

This document is the VAX-11 Text Editing Reference Manual, published by Digital Equipment Corporation in March 1980 for the VAX/VMS V02 operating system. It serves as a comprehensive reference for SOS (SON OF STOPGAP), an interactive, line-oriented text editor.

The manual details SOS's capabilities, which include:

• Creating, examining, and modifying ASCII text files.
• Searching for and replacing text strings, with an interactive "Decide mode" for case-by-case verification.
• Merging parts of files and creating subsets of files.

SOS operates in seven primary modes:

• Edit mode (*): The central mode for most commands to display and alter files.
• Input mode (nnnnn): For entering new lines of text.
• Alter mode (nnnnn): For character-by-character editing within a line.
• Alter/insert mode (none): A sub-mode of Alter for inserting text.
• Read-only mode (R*): For viewing files without making changes.
• Copy-file mode (C*): For copying text from other files.
• Decide mode (D*): For interactive decision-making during substitutions.

The editor manages text using line numbers (5-digit, up to 65535) and page numbers, allowing users to specify text by precise line/page references or relative positions using shorthand characters (e.g., . for current line, * for last line). It handles line numbering increments automatically, but these can be adjusted.

Safety features are emphasized, including confirmations before significant deletions, the "Save World" command for creating backups, and options for automatic file saving. The manual also describes SOS's use of temporary files and methods for recovering lost work after system interruptions.

Users can customize SOS's behavior through various internal parameters and switches (e.g., INCREMENT, PLINES, EXPERT, NUMBERS), which control aspects like line numbering, display output, and error message verbosity. Advanced functionalities include special pattern-matching constructs for complex search and substitute operations, and the ability to execute command files (@) to automate repetitive editing tasks.

This manual is designed as a reference for users already familiar with text editing concepts, rather than an introductory tutorial.