Date: Fri, 13 Jul 2001 19:29:35 +0400 (MSD) From: "Eugene L. Vorokov" <vel@bugz.infotecs.ru> To: Alfred Perlstein <bright@sneakerz.org> Cc: freebsd-hackers@freebsd.org Subject: Re: Some questions about kernel programming Message-ID: <200107131529.f6DFTZI00705@bugz.infotecs.ru> In-Reply-To: <20010712212809.F6664@sneakerz.org> "from Alfred Perlstein at Jul 12, 2001 09:28:09 pm"
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> /* > * return number of characters in a userland address string > * or -1 if an illegal access occurs. > */ > int > user_strlen(uaddr) > char *uaddr; > { > int ret; > > ret = -1; > do { > ch = fubyte(uaddr); > ret++; > } while (ch != 0 && ch != -1); > > return (ch == -1 ? -1 : ret); > } Then I don't get it. Won't this piece of code cycle forever fetching first byte of the string again and again ? According to fetch(9) fubyte() doesn't change uaddr, or am I missing something again ? Am I allowed to do uaddr++ for userspace addresses in such a case ? Regards, Eugene To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message
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