The most widely-known version, CORAL 66, was subsequently developed by I. F. Currie and M. Griffiths under the auspices of the Inter-Establishment Committee for Computer Applications (IECCA).
"[8][9] As Coral was aimed at a variety of real-time work, rather than general office data processing, there was no standardised equivalent to a stdio library.
IECCA recommended a primitive input/output (I/O) package to accompany any compiler (in a document titled Input/Output of Character data in Coral 66 Utility Programs).
Source code for a Coral 66 compiler (written in BCPL) has been recovered and the Official Definition of Coral 66 document by Her Majesty's Stationery Office (HMSO) has been scanned; the Ministry of Defence patent office has issued a licence to the Edinburgh Computer History project to allow them to put both the code and the language reference online for non-commercial use.
A variant of Coral 66 named PO-CORAL was developed during the late 1970s to early 1980s by the British General Post Office (GPO), together with GEC, STC and Plessey, for use on the System X digital telephone exchange control computers.