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diff --git a/lib/liblwres/man/lwres.3 b/lib/liblwres/man/lwres.3 deleted file mode 100644 index f2393912d..000000000 --- a/lib/liblwres/man/lwres.3 +++ /dev/null @@ -1,158 +0,0 @@ -.\" -.\" Copyright (C) 2000, 2001 Internet Software Consortium. -.\" -.\" Permission to use, copy, modify, and distribute this software for any -.\" purpose with or without fee is hereby granted, provided that the above -.\" copyright notice and this permission notice appear in all copies. -.\" -.\" THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM -.\" DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL -.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL -.\" INTERNET SOFTWARE CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, -.\" INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING -.\" FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, -.\" NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION -.\" WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. -.\" -.TH "LWRES" "3" "Jun 30, 2000" "BIND9" "" -.SH NAME -lwres \- introduction to the lightweight resolver library -.SH SYNOPSIS -\fB#include <lwres/lwres.h>\fR -.SH "DESCRIPTION" -.PP -The BIND 9 lightweight resolver library is a simple, name service -independent stub resolver library. It provides hostname-to-address -and address-to-hostname lookup services to applications by -transmitting lookup requests to a resolver daemon -\fBlwresd\fR -running on the local host. The resover daemon performs the -lookup using the DNS or possibly other name service protocols, -and returns the results to the application through the library. -The library and resolver daemon communicate using a simple -UDP-based protocol. -.SH "OVERVIEW" -.PP -The lwresd library implements multiple name service APIs. -The standard -\fBgethostbyname()\fR, -\fBgethostbyaddr()\fR, -\fBgethostbyname_r()\fR, -\fBgethostbyaddr_r()\fR, -\fBgetaddrinfo()\fR, -\fBgetipnodebyname()\fR, -and -\fBgetipnodebyaddr()\fR -functions are all supported. To allow the lwres library to coexist -with system libraries that define functions of the same name, -the library defines these functions with names prefixed by -lwres_. -To define the standard names, applications must include the -header file -\fI<lwres/netdb.h>\fR -which contains macro definitions mapping the standard function names -into -lwres_ -prefixed ones. Operating system vendors who integrate the lwres -library into their base distributions should rename the functions -in the library proper so that the renaming macros are not needed. -.PP -The library also provides a native API consisting of the functions -\fBlwres_getaddrsbyname()\fR -and -\fBlwres_getnamebyaddr()\fR. -These may be called by applications that require more detailed -control over the lookup process than the standard functions -provide. -.PP -In addition to these name service independent address lookup -functions, the library implements a new, experimental API -for looking up arbitrary DNS resource records, using the -\fBlwres_getaddrsbyname()\fR -function. -.PP -Finally, there is a low-level API for converting lookup -requests and responses to and from raw lwres protocol packets. -This API can be used by clients requiring nonblocking operation, -and is also used when implementing the server side of the lwres -protocol, for example in the -\fBlwresd\fR -resolver daemon. The use of this low-level API in clients -and servers is outlined in the following sections. -.SH "CLIENT-SIDE LOW-LEVEL API CALL FLOW" -.PP -When a client program wishes to make an lwres request using the -native low-level API, it typically performs the following -sequence of actions. -.PP -(1) Allocate or use an existing \fBlwres_packet_t\fR, -called pkt below. -.PP -(2) Set \fBpkt.recvlength\fR to the maximum length we will accept. -This is done so the receiver of our packets knows how large our receive -buffer is. The "default" is a constant in -\fIlwres.h\fR: LWRES_RECVLENGTH = 4096. -.PP -(3) Set \fBpkt.serial\fR -to a unique serial number. This value is echoed -back to the application by the remote server. -.PP -(4) Set \fBpkt.pktflags\fR. Usually this is set to 0. -.PP -(5) Set \fBpkt.result\fR to 0. -.PP -(6) Call \fBlwres_*request_render()\fR, -or marshall in the data using the primitives -such as \fBlwres_packet_render()\fR -and storing the packet data. -.PP -(7) Transmit the resulting buffer. -.PP -(8) Call \fBlwres_*response_parse()\fR -to parse any packets received. -.PP -(9) Verify that the opcode and serial match a request, and process the -packet specific information contained in the body. -.SH "SERVER-SIDE LOW-LEVEL API CALL FLOW" -.PP -When implementing the server side of the lightweight resolver -protocol using the lwres library, a sequence of actions like the -following is typically involved in processing each request packet. -.PP -Note that the same \fBlwres_packet_t\fR is used -in both the \fB_parse()\fR and \fB_render()\fR calls, -with only a few modifications made -to the packet header's contents between uses. This method is recommended -as it keeps the serial, opcode, and other fields correct. -.PP -(1) When a packet is received, call \fBlwres_*request_parse()\fR to -unmarshall it. This returns a \fBlwres_packet_t\fR (also called pkt, below) -as well as a data specific type, such as \fBlwres_gabnrequest_t\fR. -.PP -(2) Process the request in the data specific type. -.PP -(3) Set the \fBpkt.result\fR, -\fBpkt.recvlength\fR as above. All other fields can -be left untouched since they were filled in by the \fB*_parse()\fR call -above. If using \fBlwres_*response_render()\fR, -\fBpkt.pktflags\fR will be set up -properly. Otherwise, the LWRES_LWPACKETFLAG_RESPONSE bit should be -set. -.PP -(4) Call the data specific rendering function, such as -\fBlwres_gabnresponse_render()\fR. -.PP -(5) Send the resulting packet to the client. -.PP -.SH "SEE ALSO" -.PP -\fBlwres_gethostent\fR(3), -\fBlwres_getipnode\fR(3), -\fBlwres_getnameinfo\fR(3), -\fBlwres_noop\fR(3), -\fBlwres_gabn\fR(3), -\fBlwres_gnba\fR(3), -\fBlwres_context\fR(3), -\fBlwres_config\fR(3), -\fBresolver\fR(5), -\fBlwresd\fR(8). |