04 1973AsmRef link-10

This document is the Programmer's Reference Manual for LINK-10, the DECsystem-10 Linking Loader, published in May 1973.

It describes LINK-10 as a system utility program designed to merge independently-translated object modules (.REL files) into a single executable program (core image). Its core functions include relocating code to actual memory locations, resolving symbols and linking with required libraries, and supporting program debugging.

Users can interact with LINK-10 in two primary ways:

1. Automatically: Through high-level system commands like LOAD, EXECUTE, or DEBUG, which the COMPIL program interprets to drive LINK-10 with default settings.
2. Directly: By issuing the R LINK system command, providing interactive, fine-grained control over the loading process using extensive "switches."

LINK-10's primary output is the executable core image, which can be executed immediately or saved (as .SAV, .SHR, .LOW, .HGH files) for future use. It also generates auxiliary output files, such as map, log, symbol, and expanded core image (XPN) files, to assist in program debugging. The manual details various switches that offer control over features like memory allocation, symbol table management, message verbosity, and file operations, including an overlay facility for large programs.

The document emphasizes that LINK-10 is a new, more sophisticated, and flexible program compared to its predecessor, the LOADER program, offering enhanced capabilities for managing program linkages on the DECsystem-10.