Embedded Systems/Terminate and Stay Resident

From Wikibooks, open books for an open world
< Embedded Systems
Jump to: navigation, search

In the original DOS operating system, there was no capability for multi-threading, or multi-process mechanisms. However, it was found to be very beneficial to leave certain components in memory even after the process that created it ended. These program fragments were known as Terminate and Stay Resident modules, and were the precursors to the dynamic library infrastructure of current Windows operating systems. TSR routines are often used to implement device drivers, or common library functions.