[HECnet] Slightly OT - How to concatenate multi line strings in DEC COBOL

[Sampsa Laine]

All I need is a function in C that takes a string and computes it's SHA1 hash (I've got the code for this) and returns the SHA1 hash as a string, I was thinking along the lines of

int sha1hash(char *stringToHash, char *hashStringOutput);	/* returns -1 if something borks, otherwise 0 */

Anyone got a nice little bit of code for:

a) Wrapping that with the OpenVMS calling standard stuff in C (the strings will be passed in as descriptors etc, so I need to "unpack" them I suppose)

b) An example call from COBOL to that wrapper..

Anyone? :)

Sampsa

On 13 Sep 2012, at 14:01, Mark Wickens wrote:

On 13/09/12 01:33, Jordi Guillaumes i Pons wrote:
It should be no problem. All the DEC compilers share a common ABI (VMS calling and condition handling standard). There is a manual in the "gray wall" just about that. I can't search for it now, but iirc the title is easy to pick up.

Basic summary: scalars are passed by reference, strings are passed by descriptor address. VMS C provides macros to build and manage descriptors (the ASCIZ convention is fortunately not used).

The HP OpenVMS Calling Standard manual I think is what you are referring to.
Unfortunately I don't think it's going to help Sampsa much - I had a quick flick through and it's all low level detail, it doesn't contain any examples of calling one language from another. More of a specification of the interface for new language implementations.

Mark

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