Re: segfault in pcap_snapshot

[Guy Harris <gharris () sonic net>]

On Sun, Feb 22, 2004 at 11:35:21PM +0100, Karl Sjödahl wrote:
> if(pcap_open_live(device, BUFSIZ, PROMISC, 0, errbuf) == -1)
> {
>                       error handling
> }

"pcap_open_live()" doesn't return an integer, it returns a "pcap_t *" on
success, and NULL on failure; the "pcap_t *" is what you have to use in
subsequent calls to "pcap_compile()", "pcap_setfilter()",
"pcap_dispatch()"/"pcap_loop()"/"pcap_next()", etc..

Thus, that call should be

        p = pcap_open_live(device, BUFSIZ, PROMISC, 0, errbuf);
        if (p == NULL
        {
                error handling
        }

and that "p" (which should be a "pcap_t *") is what should be used in
subsequent calls such as

> if(pcap_compile(p, &filter_code, TESTFILTER, 0, netmask) == -1)
> {
>                       error handling    
> }
> if(pcap_setfilter(p, &filter_code) == -1)
> {
>                       error handling
> }
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