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). Jordi Guillaumes i Pons Barcelona - Catalunya - Europa El 12/09/2012, a les 20:21, Sampsa Laine <sampsa at mac.com> va escriure: Ah, That for example calling C from COBOL is for OSF/1 only. I wonder how one does this on VMS.. Sampsa On 12 Sep 2012, at 21:10, Michael Young wrote: found this at odl.sysworks.biz/disk$axpdocdec971/progtool/d37aaa48.p341.bkb#2110 : Example 12-8: C Include File " cobfunc " void cobcancel ( /* CANCEL the named COBOL routine */ char *name ); int cobcall ( /* Call a COBOL program from a C routine */ char *name, /* READ: name of the program */ int argc, /* READ: how many arguments */ char **argv /* READ: array of pointers to the arguments */ ); int cobfunc ( /* Call a COBOL program from a C routine, then CANCEL it */ char *name, /* name of the program */ int argc, /* how many arguments */ char **argv /* array of pointers to the arguments */ ); #ifdef __osf__ void cob_init ( /* init the RTL */ int argc, /* argument count */ char **argv, /* arguments */ char **envp /* environment variable pointers */ ); #endif --Mike On Sep 12, 2012, at 1:54 PM, Sampsa Laine <sampsa at mac.com> wrote: Does anybody happen to have a nice sample bit of code on how to call a C function from DEC COBOL? The documentation gave me this code: /* crtn - c function to test use of argc and argv in c routines * called from HP COBOL */ #include "cobfunc.h" #include <stdio.h> extern int _ _Argc; extern char **_ _Argv[]; #define argc _ _Argc #define argv (*_ _Argv) void crtn() { int i; i = 0; for (i = 0; i < argc; i++) { printf("argv[%d] = %s\n", i, argv[i]); } } But I can't find cobfunc.h anywhere Sampsa On 12 Sep 2012, at 20:18, Sampsa Laine wrote: Well this whole COBOL thing is verging on the humour value anyway, I think I might leave that til later :) Sampsa On 12 Sep 2012, at 20:13, Jordi Guillaumes i Pons wrote: IIRC there was no screen section support in VAX COBOL. Perhaps this can be a good excuse to learn the SMG$ RTL routines... Jordi Guillaumes i Pons Barcelona - Catalunya - Europa El 12/09/2012, a les 17:10, Sampsa Laine <sampsa at mac.com> va escriure: Tried to compile my little program on GORVAX but it has problems with the SCREEN SECTION that works on the AXP version.. I'm thinking I must have an old compiler or something. Anyone know what the latest is? Anyone have a kit? Sampsa Michael Young young at ecn.purdue.edu