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Date: Fri, 16 May 2008 16:19:38 +0200 (CEST)
From: Wojciech Puchar <wojtek@wojtek.tensor.gdynia.pl>
To: Steve Randall <srandall52@sbcglobal.net>
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Cc: freebsd-questions@freebsd.org
Subject: Re: Unable to talk to tap(4)
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>>>>>  unsigned char * buffer = (unsigned char*)malloc(1514);

is stdlib.h included (i'm asking for sure)?

>>>>>  if (buffer = NULL) {
>
>       if (buffer == NULL) {
>
>
>>>>>    fprintf (stderr, "No memory available.\n");
>>>>>    close (tapFD);
>>>>>    exit(3);
>>>>>  }
>>
>> When I replace the malloc with an automatic array, the
>> error goes away and I get the data I am looking for. i.e.:
>>
>>    unsigned char buffer[1514];
>>
>> So why can't I use malloc to create that buffer?

anyway not using malloc is good habit :) but it should work anyway.
try


buffer[0]=buffer[1513]=0;

to make sure page is actually allocated.

if this help - maybe tap driver is buggy.