Pointers to functions on Xenix

[Steve Resnick]

I have a shell I am writing for MS DOS which  will extend the batch language
and add some UNIX style enhancements (aliasing, history, and getting rid of
that damn backslash). As I write this I want to port it to UNIX/Xenix as well.
my problem is that the Xenix C compiler bitches at using pointers to
functions. For example, consider the follow fragment...

int echo(int, char **);		/* The protos allow the forward refernce to */
int setenv(int, char **);	/* the functions */

struct ci 				/* This is the command table */
{		
	char * name;			/* The shell uses this name to compare
					   against the entered command */
	int (* fptr)(int, char **);	/* and here is the function pointer */
}  Cmds[] =
"ECHO",echo,
"SET",setenv,
} ;
.
.	/* Main and other stuff here */
.
.
/* When I get to the point where I execute an internal function, I call the
   routine here..
*/
	(Cmds[idx].fptr)(c,v);	/* Here is where I call  the function */

This is what the compiler doesn't like. The error message is something like

Term does not evaluate to a function.

This seems to be legitimate C in the MS DOS world...
Help! Please!