Re: Accessing SNL Function and global Pvs from C

[Benjamin Franksen <benjamin.franksen@helmholtz-berlin.de>]

On Monday, February 24, 2014 22:45:19 Ganesh Jangir wrote:
> Dear All,
>
>  Facing problem in calling/accessing SNL Function and global Pvs from
> C. Here is the example I  tried.
>  _________________________________________________________________
>
>
>  program cmcseq
>
>
>  string CMC_STATUS;
>  assign CMC_STATUS to "CMC_STATUS";
>
>
>
> foreign ssId;
>
>
>  // No monitoring
>  // No options
>  ....
>
>
>  ss ss1 {
>  state initial{
>  when(delay(5)){
>  	  printf("Calling cmcStatus... \n");
>  	  cmcStatus(ssId,"Hello",pvIndex(CMC_STATUS));
>
>  	  printf("Received status is %s\n", CMC_STATUS);
>  	 }state default
>             }
>  ....
>  }
>
>
>  C Function is
>  %%#include <stdio.h>
>  %%#include <string.h>
>  %%#include <stdlib.h>
>  %{
>
>  void cmcStatus(SS_ID ssId,string msg, VAR_ID pvCmcStatus) {
>
>  	strcpy(pvCmcStatus,msg);
>  	seq_pvPut(ssId,pvCmcStatus, ASYNC);
>  	}
>  }%

Try to move the #include stuff (and a prototype for your function) to
the top:

program cmcseq

%%#include <stdio.h>
%%#include <string.h>
%%#include <stdlib.h>
%%void cmcStatus(SS_ID ssId,string msg, VAR_ID pvCmcStatus);

The relevant section in the manual is http://www-
csr.bessy.de/control/SoftDist/sequencer/Reference.html#defining-c-
functions-within-the-program where it says:

"""
It matters where the function is defined: if it appears at the end of
the program, it can see all the variable and type definitions generated
by the SNL compiler, so if your C function accesses a global SNL
variable, you must place its definition at the end. However, this means
that the generated code for the SNL program does not see the C function
definition, so you might want to place a separate prototype for the
function in the definitions section (i.e. before the state sets).
"""

Cheers
Ben

>
>
>  During Make Warnings are
>  ;
>      ^
>  ../cmcseq.stt:49:4: warning: implicit declaration of function
> &#8216;cmcStatus&#8217; [-Wimplicit-function-declaration]
> cmcStatus("ss1","Hello",CMC_STATUS);
>      ^
>  .
>  .
>  .
>  ../cmcseq.stt:149:6: warning: conflicting types for
> &#8216;cmcStatus&#8217; [enabled by default] void cmcStatus(SS_ID
> ssId,string msg, VAR_ID pvCmcStatus) { ^
>  ../cmcseq.stt:49:4: note: previous implicit declaration of
> &#8216;cmcStatus&#8217; was here cmcStatus("ss1","Hello",CMC_STATUS);
>      ^
>  ../cmcseq.stt: In function &#8216;cmcStatus&#8217;:
>  ../cmcseq.stt:151:3: warning: passing argument 1 of
> &#8216;strcpy&#8217; makes pointer from integer without a cast
> [enabled by default] strcpy(pvCmcStatus,msg);
>     ^  printf("checking if all are connected USE pvConnecetd Count
> Function, Wait UNTIL lISTED PVS are c  printf("checking if all are
> connected USE pvConnecetd Count Function, Wait UNTIL lISTED PVS are
> connected  \n"); /*  configure(&seq,&version);
>  	  printf("Read Configuration parameter here, Calling File Read
> function %d %f \n", seq, version); */onnected  \n");
>  	/*  configure(&seq,&version);
>  	  printf("Read Configuration parameter here, Calling File Read
> function %d %f \n", seq, version); */
>  In file included from cmcseq.c:4:0:
>  /usr/include/string.h:125:14: note: expected &#8216;char *
> __restrict__&#8217; but argument is of type &#8216;VAR_ID&#8217;
> extern char *strcpy (char *__restrict __dest, const char *__restrict
> __src) ^
>  /usr/bin/ar -rc   libCMC_SEQSupport.a        initTrace.o cmcseq.o
>  /usr/bin/ranlib libCMC_SEQSupport.a
>
>
>
>
>  The error during run time is .
>  seq cmcseq,
>  Sequencer release 2.1.16, compiled Sat Feb 22 20:11:22 2014
>  Spawning sequencer program "cmcseq", thread 0xd939e0: "cmcseq"
>  cmcseq[0]: all channels connected & received 1st monitor
>  epics> Calling cmcStatus...
>  Segmentation fault (core dumped)
>
>
>
>
>
>
>  Also, Where can I found  sequencer Examples /tutorial, for accessing
> SNL_Function and Pvs in C. I am referring to Sequencer User Guide
> 2.1.16,already.
>
>
> Thanks and Regards
>
> Ganesh Jangir
>
> =====-----=====-----====> Notice: The information contained in this e-mail
> message and/or attachments to it may contain
> confidential or privileged information. If you are
> not the intended recipient, any dissemination, use,
> review, distribution, printing or copying of the
> information contained in this e-mail message
> and/or attachments to it are strictly prohibited. If
> you have received this communication in error,
> please notify us by reply e-mail or telephone and
> immediately and permanently delete the message
> and any attachments. Thank you
--
"Make it so they have to reboot after every typo." ― Scott Adams

Attachment: signature.asc
Description: This is a digitally signed message part.