Path: utzoo!attcan!uunet!lll-winken!lll-tis!ames!umd5!brl-adm!cmcl2!phri!manhat!mancol!marob!daveh
From: daveh@marob.MASA.COM (Dave Hammond)
Newsgroups: comp.lang.c
Subject: Casting function ptrs
Message-ID: <281@marob.MASA.COM>
Date: 18 May 88 20:48:37 GMT
Reply-To: daveh@marob.UUCP (Dave Hammond)
Organization: 18th Street Construction Co NY NY
Lines: 43


Given a list of varying typed functions, their names and addresses:

struct funcs {
    char *name;
    unsigned (*func)();
}
char *foo();
struct funcs f = {  "foo", (char *)foo };

And a routine which is passed a function name in order to lookup and return
its associated address: 

unsigned *lookup_func(name)
char *name;
{
  ...
  return( (unsigned *) f->func );
}

How does one declare the lookup function, the return address variable and
call the returned function, while properly casting the function return value?
I'm doing it like so:

unsigned *lookup_func();
unsigned *(*func)();
char *retp;

if ((func = lookup_func("foo")) != (unsigned *)0) {
    if (( retp = (char *) (*func)() ))
	printf("retp=%s",retp);
    }

Yes? No? Gonna blow up on me at some point ?


Dave Hammond
DSI Communications, Inc.
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