Date: Thu, 16 Mar 2000 21:31:06 +0000 From: David Malone <dwmalone@maths.tcd.ie> To: hackers@freebsd.org Subject: T/TCP friendly inetd change? Message-ID: <200003162131.aa50415@salmon.maths.tcd.ie>
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I was reading a little about T/TCP in Steven's book, and it occured to me that some of inetd's small services would be ideal candidates for T/TCP. (auth, time and daytime in particular). According to Stevens, the main thing you need to do to make a server T/TCP firendly is use the MSG_EOF flag when you send the last block of data to that socket. For each of these services, which only write a single block of data, this involves just changing: write(s, buf, len); to: send(s, buf, len, MSG_EOF); I've tried this over my slip link and it does seem to reduce the number of packets sent by 2 for telnetting to the daytime port. I also had a look at fetch (the only thing in the tree which uses MSG_EOF at the moment), which has an option for turning off the MSG_EOF stuff 'cos some buggy http servers don't like half closed connections. I don't think this applies in this case 'cos we're on the server side - not the client side, and the client expects an EOF anyway. Would this be an acceptable patch to inetd? It would be nice to encourage the use of T/TCP within FreeBSD, as we seem to be the only people who have it ;-) David. --- builtins.c 2000/03/11 11:28:07 1.19 +++ builtins.c 2000/03/16 21:20:02 @@ -219,7 +219,7 @@ clock = time((time_t *) 0); (void) sprintf(buffer, "%.24s\r\n", ctime(&clock)); - (void) write(s, buffer, strlen(buffer)); + (void) send(s, buffer, strlen(buffer), MSG_EOF); } /* @@ -320,7 +320,7 @@ syslog(LOG_ERR, "asprintf: %m"); exit(EX_OSERR); } - write(s, p, strlen(p)); + send(s, p, strlen(p), MSG_EOF); free(p); exit(0); @@ -602,7 +602,7 @@ syslog(LOG_ERR, "asprintf: %m"); exit(EX_OSERR); } - write(s, p, strlen(p)); + send(s, p, strlen(p), MSG_EOF); free(p); exit(0); @@ -664,7 +664,7 @@ unsigned long result; result = machtime(); - (void) write(s, (char *) &result, sizeof(result)); + (void) send(s, (char *) &result, sizeof(result), MSG_EOF); } /* To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message
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