PRIMOS

At first, this language was FORTRAN IV,[6] which was an odd choice from a pure computer science standpoint: no pointers, no native string type, etc.

Honeywell, at that time, was uninterested in minicomputers, so they left and founded Prime, "taking" the code with them.

For example, around 1990, the University of Salford in the UK, modified the PRIMOS running on its five 9955 systems so that undergraduates could no longer use the MESSAGE command, that wrapped the PRIMOS SMSG$() call, to send messages to other undergraduates, because online "chatting" using that command was becoming rife, tying up terminals from the limited pool available.

By this time, a company called Peritus (which employed a number of ex-Prime engineers) was maintaining PRIMOS.

From Revision 19, major portions of PRIMOS were written in the languages SPL and Modula-2, the usage of the Prime Macro Assembler _(PMA), FORTRAN IV and PL/P declined considerably around this time.

[15] This interpreted language, bearing similarities to Pascal, was both accessible to novice users and capable of powerful command line automation.

ESRI used PRIMOS CPL as a basis for the platform-independent scripting languages AML (for ArcInfo) and SML (PC-ARC/INFO).

One notable feature was the MIRROR_ON command, which facilitated the creation of a pair of logically equivalent, identical partitions that were maintained in real-time.

Unlike RAID 1, which typically requires specific hardware support for disk mirroring, the MIRROR_ON command implemented this functionality at the software level, offering a flexible and cost-effective solution for data redundancy.

[19] Released similar timing to PRIMENET,[20] [21] it enabled high-speed local area networking.