GCC problem

westymatt · External Since: Jul 15, 2007 Posts: 5

I switched my code over to using what I believe to be the K&R style
function definitions.

63 /*pcap_loop callback routine*/
64 void
65 capture_callback(buffer, packet_header, data)
66 u_char *buffer, const struct pcap_pkthdr
*packet_header, u_char *data;
67 {
68 total_captured_packets++;
69 if (display == true)
70 {
71 fprintf(stdout, "Received packet %d\n");
72 }
73 if (cache_packets == true)
74 {
75 struct packetCache *pc;
76 if ((pc = malloc(sizeof *pc + packet_header->len)) ==
NULL)
77 {
78 fprintf(stderr, "Memory Allocation Error!\n");
79 fprintf(stderr, "Turning off caching\n");
80 cache_packets = false;
"packman.c" 230L, 5444C written
sysadmin@devbox:~/projects/packet_capture$ gcc -c packman.c
packman.c: In function âcapture_callbackâ:
packman.c:66: error: expected identifier or â(â before âconstâ
packman.c:76: error: invalid type argument of â->â

Ulrich Eckhardt · External Since: Jul 30, 2004 Posts: 83

westymatt wrote:
> I switched my code over to using what I believe to be the K&R style
> function definitions.

That would be incredibly stupid. The simple reason is that it's
old&deprecated and non-standard. Any compiler worth its name should reject
it, unless explicitly instructed to do otherwise.

Uli

Mike McGInn · External Since: Jul 18, 2007 Posts: 1

On Wed, 18 Jul 2007 07:19:17 +0000, westymatt wrote:

> I switched my code over to using what I believe to be the K&R style
> function definitions.
>
> 63 /*pcap_loop callback routine*/
> 64 void
> 65 capture_callback(buffer, packet_header, data)
> 66 u_char *buffer, const struct pcap_pkthdr
> *packet_header, u_char *data;
> 67 {
> 68 total_captured_packets++;
> 69 if (display == true)
> 70 {
> 71 fprintf(stdout, "Received packet %d\n");
> 72 }
> 73 if (cache_packets == true)
> 74 {
> 75 struct packetCache *pc;
> 76 if ((pc = malloc(sizeof *pc + packet_header->len)) ==
> NULL)
> 77 {
> 78 fprintf(stderr, "Memory Allocation Error!\n");
> 79 fprintf(stderr, "Turning off caching\n");
> 80 cache_packets = false;
> "packman.c" 230L, 5444C written
> sysadmin@devbox:~/projects/packet_capture$ gcc -c packman.c
> packman.c: In function âcapture_callbackâ:
> packman.c:66: error: expected identifier or â(â before âconstâ
> packman.c:76: error: invalid type argument of â->â

You should buy the second edition before doing that.

--
Mike McGinn
"more kidneys than eyes!"

Gil Hamilton · External Since: Jan 08, 2007 Posts: 22

westymatt <westymatt RemoveThis @gmail.com> wrote in news:1184743157.214777.263570
@z28g2000prd.googlegroups.com:

> I switched my code over to using what I believe to be the K&R style
> function definitions.

As others have already noted, that's not a terribly sane thing to do. I
really can't imagine why you would want to do so. However gcc will still
happily accept the code if you give it proper K&R syntax.

> 63 /*pcap_loop callback routine*/
> 64 void
> 65 capture_callback(buffer, packet_header, data)
> 66 u_char *buffer, const struct pcap_pkthdr
> *packet_header, u_char *data;

The function arguments should be separated by semicolons:

void capture_callback(buffer, packet_header, data)
u_char *buffer;
const struct pcap_pkthdr *packet_header;
u_char *data;
{
/* function body */
}

Also, you should know that the keywords "const" and "void" did not exist
back in original K&R days.

GH