Mainframe, MVS and zOS Discussion

Hi,

In which language mainframe base software is written? I thought it might be COBOL but it dos nto look like. Where can I get this information, please advise.

Depending on what you mean by 'base' software the answer could be assembly language or C or some other low-level language.

A typical mainframe runs z/OS (although z/VM and others are also available). In addition, the typical mainframe runs JES2 or JES3, a security package (RACF or TOP SECRET or ACF2 most likely), VTAM, HSM, TSO, CICS, a database product, SMS, SDSF (or other output management software), LLA, CSV, VLF, TCPIP, and usually a fair number of other system products. In the most restrictive case, you could consider z/OS as the "base" software -- although you cannot do much with it unless some of the other products are running (for example, to log onto a TSO session TSO has to be running along with VTAM and possibly TCPIP depending upon the connection type between the terminal and the mainframe).

Mainframe products are written in assembler or C or PL/X (a language IBM developed explicitly for coding system functions) to allow access to some of the low-level functions and control blocks used by the system.

Thanks forthe answers.

I was talking about zOS as "base software". As UNIX is written in C.

And was curious to know about COBOL too that in what language it is written?

And was curious to know about COBOL too that in what language it is written?

In whatever language, or mix of languages, the vendor decides - including COBOL itself.