The PL/I language and the MVT PL/I F compiler - M18

[@michaelyapkf]

FYI. PL/I began life as part of an attempt to unify business and scientific computing. In the early 1960s, business computing was being done mostly in COBOL, while developers in science, math, and academia were mostly using Fortran. Even the hardware used by the two communities was different. IBM wanted move everyone onto a common hardware platform (the System/360 ), and wanted a common programming language to go along with it. The team tasked with creating this common language initially attempted to begin with Fortran and extend it to add the required features from COBOL. This proved unsuccessful, and they began work on a new language altogether, based loosely on ALGOL. The new language was briefly named NPL ("new programming language"), and then MPPL ("Multi-purpose programming language"), and then finally PL/I. The first description of the language (still called NPL) was released in 1964. The first compiler came out in 1966. In 1967 work began writing a complete specification of the language. Excerpt from www.whoishostingthis.com/resources/pl-i/

[@archivesinformatiques9567]

There are two small errors in the code you publish in github. 1st The first line starts in column 1, but PL/I(F) source code expect source code col 2 to 72 2nd You declare array A EXTERNAL twice with different sizes, A(35) and A(50). PL/I(F) tolerates it, but the more recent versions of the compiler reject it b rgds from the PL/I(F) and MVS 3.8 interest group

[@moshixmainframechannel]

First column: well known. It’s the ascii editors that move it one to the left. Double declaration, yes it shouldn’t be there

[@saf271828]

BCPL was invented by Dr. Martin Richards in University of Cambridge, UK. Kernighan took BCPL to create B, which with Dennis Ritchie, was evolved to C. K&R had no involvment with the creation of BCPL.

[@saf271828]

Additionally, BCPL is derived from CPL, which was derived directly from Algol; PL/I was not in its lineage.

[@moshixmainframechannel]

Thanks for pointing that out. And for watching the video

[@saf271828]

No worries; I love watching mainframe videos; it's such a fascinating architecture (hardware-wise and software-wise) to me.

[@SergioLindo]

Hi, I tought that Dennis Ritchie and Ken Thompson invented B, then Dennis Ritchie invented C, then Ken Thompson invented Unix, then Brian Kernighan contributed to Unix and was the driving force and co-creator of the C programming book. At least that is the official story that you find everywhere. Do you mean that the official story is not entirely true? Do you mean a different Kernighan? Best regards