There is a frequent poster on one of the language specific board who seems to enjoy attacking people for their ignorance, and also attacking people who's opinions differ from his/her own. He/She belittles people and tells others to disregard information provided by those people. (For the rest of this posting, I'm going to assume that the person in question is a male, as it make the writing easier.)
Once he wrote a fairly nasty response to one of my responses to a query where I'd mistyped something (left out a '&' in one of my calls, thus making the code snippet non-functional). He didn't say "the scanf() function in filker0's post is missing a '&'", rather he attacked the post and by implication the competance of the poster. When I saw the post, I fixed my posting and sent him an e-mail. Within that e-mail, I made the mistake of pointing out that I've probably been programming in C longer than he has. (I've been programming in C since 1980, and was involved with the ANSI C committee for C89.) This was a private communication, and I never attacked him, either in the e-mail nor in the forum, but he seems to have taken it upon himself to be as rude and dismissive as possible whenever he responds to my posting. He also quoted, out of context, my assertion that I've probably been programming in C longer than he has, in order to bolster his public dismissal of me as an incompetant egomaniac in response to another posting that I made.
I've tried simply ignoring this person. I've tried not to get personal. I've tried not to let it get to me. But it has gotten in the way of the reason I post in the first place -- to help people who need help. I've become reluctant to post replies to anything this person replies to before I do, since he seems to take offense and throw more fuel on the fire of his on-line distaste for me.
Advice on how to deal with these situations will be appreciated.