LINK *HWORLD=HWORLD *^Z .R HWORLD.SAV Hello World Press Control-T for 1 line status: 1 KB0 HWORLD+RT11 KB(0R) 2(28)K+4K 0.6(+0.2) +0 ..DIR HWORLD.*/na/ex/si/pr SY:[1,2] HWORLD.BAS 1 < 60> HWORLD.BAC 7C <124> HWORLD.TSK 25C <124> HWORLD.MAC 1 < 60> HWORLD.OBJ 1 < 60> HWORLD.SAV 2C <124> Total of 37 blocks in 6 files in SY:[1,2] . TECO (Text Editor and COrrector) The TECO editor was itself implemented as an RTS to maximize the amount of memory available for the editing buffer, and also because it was first implemented in RSTS V5B, before the release of the general purpose runtime systems (RSX and RT11). TECO was the only RTS distributed with RSTS that did not contain a built-in KBM. The user would start up TECO (like any other program) by running a TECO program (TECO.TEC). TECO and the affine QEDIT were the direct ancestors of the first UNIX-based text editor, ED. Most RSTS systems used CCL's to create a file (MAKE filespec), edit a file (TECO filespec), or run a TECO program (MUNG filespec, data). The following program is an example of how TECO could be used to calculate pi (currently set to 20 digits): Ready run TECO *GZ0J\UNQN"E 20UN ' BUH BUV HK QN< J BUQ QN*10/3UI QI< \ +2*10+(QQ*QI)UA B L K QI*2-1UJ QA/QJUQ QA-(QQ*QJ)-2\ 10@I// -1%I > QQ/10UT QH+QT+48UW QW-58"E 48UW %V ' QV"N QV^T ' QWUV QQ-(QT*10)UH > QV^T @^A/ /HKEX$$ 31415926535897932384 Ready RSTS easter eggs System start-up (INIT.SYS) If a user typed an unrecognized command at system boot to the "Option:" prompt of INIT.SYS, the startup utility, the message "Type 'HELP' for help" was displayed. If the user subsequently typed 'HELP' (including the quotes) to the prompt, the response was "How amusing, anyway..." followed by the actual help message. PDP-11 console lights A system manager could compile into the kernel a rotating display pattern that gave the illusion of two snakes chasing each other around the console lights. The normal kernel would give the illusion of one snake moving from right to left in the data lights across the bottom. If the system manager also compiled the "lights" object module the user would see an additional snake moving from left to right in the address lights across the top. This was accomplished by using supervisory mode in the versions prior to 9.0. RSX also had a similar display pattern that would appear as if two snakes were playing