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diff --git a/adns-0.6/src/adns.h b/adns-0.6/src/adns.h
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+/*
+ * adns.h
+ * - adns user-visible API (single-threaded, without any locking)
+ */
+/*
+ *
+ *  This file is
+ *    Copyright (C) 1997-1999 Ian Jackson <ian@davenant.greenend.org.uk>
+ *
+ *  It is part of adns, which is
+ *    Copyright (C) 1997-1999 Ian Jackson <ian@davenant.greenend.org.uk>
+ *    Copyright (C) 1999 Tony Finch <dot@dotat.at>
+ *  
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2, or (at your option)
+ *  any later version.
+ *  
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ * 
+ *  For the benefit of certain LGPL'd `omnibus' software which provides
+ *  a uniform interface to various things including adns, I make the
+ *  following additional licence.  I do this because the GPL would
+ *  otherwise force either the omnibus software to be GPL'd or for the
+ *  adns-using part to be distributed separately.
+ *  
+ *  So, you may also redistribute and/or modify adns.h (but only the
+ *  public header file adns.h and not any other part of adns) under the
+ *  terms of the GNU Library General Public License as published by the
+ *  Free Software Foundation; either version 2 of the License, or (at
+ *  your option) any later version.
+ *  
+ *  Note that adns itself is GPL'd.  Authors of adns-using applications
+ *  with GPL-incompatible licences, and people who distribute adns with
+ *  applications where the whole distribution is not GPL'd, are still
+ *  likely to be in violation of the GPL.  Anyone who wants to do this
+ *  should contact Ian Jackson.  Please note that to avoid encouraging
+ *  people to infringe the GPL as it applies the body of adns, I think
+ *  that if you take advantage of the special exception to redistribute
+ *  just adns.h under the LGPL, you should retain this paragraph in its
+ *  place in the appropriate copyright statements.
+ *
+ *
+ *  You should have received a copy of the GNU General Public License,
+ *  or the GNU Library General Public License, as appropriate, along
+ *  with this program; if not, write to the Free Software Foundation,
+ *  Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ *
+ *  $Id: adns.h,v 1.1.1.1 2000-02-16 17:32:46 sdyoung Exp $
+ */
+
+#ifndef ADNS_H_INCLUDED
+#define ADNS_H_INCLUDED
+#ifdef __cplusplus
+extern "C" { /* I really dislike this - iwj. */
+#endif
+
+#include <stdio.h>
+
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <sys/types.h>
+#include <sys/time.h>
+#include <unistd.h>
+
+/* All struct in_addr anywhere in adns are in NETWORK byte order. */
+
+typedef struct adns__state *adns_state;
+typedef struct adns__query *adns_query;
+
+typedef enum {
+  adns_if_noenv=        0x0001, /* do not look at environment */
+  adns_if_noerrprint=   0x0002, /* never print output to stderr (_debug overrides) */
+  adns_if_noserverwarn= 0x0004, /* do not warn to stderr about duff nameservers etc */
+  adns_if_debug=        0x0008, /* enable all output to stderr plus debug msgs */
+  adns_if_logpid=       0x0080, /* include pid in diagnostic output */
+  adns_if_noautosys=    0x0010, /* do not make syscalls at every opportunity */
+  adns_if_eintr=        0x0020, /* allow _wait and _synchronous to return EINTR */
+  adns_if_nosigpipe=    0x0040, /* applic has SIGPIPE set to SIG_IGN, do not protect */
+  adns_if_checkc_entex= 0x0100, /* do consistency checks on entry/exit to adns funcs */
+  adns_if_checkc_freq=  0x0300  /* do consistency checks very frequently (slow!) */
+} adns_initflags;
+
+typedef enum {
+  adns_qf_search=          0x00000001, /* use the searchlist */
+  adns_qf_usevc=           0x00000002, /* use a virtual circuit (TCP connection) */
+  adns_qf_owner=           0x00000004, /* fill in the owner field in the answer */
+  adns_qf_quoteok_query=   0x00000010, /* allow quote-requiring chars in query domain */
+  adns_qf_quoteok_cname=   0x00000000, /* allow ... in CNAME we go via - now default */
+  adns_qf_quoteok_anshost= 0x00000040, /* allow ... in things supposed to be hostnames */
+  adns_qf_quotefail_cname= 0x00000080, /* refuse if quote-req chars in CNAME we go via */
+  adns_qf_cname_loose=     0x00000100, /* allow refs to CNAMEs - without, get _s_cname */
+  adns_qf_cname_forbid=    0x00000200, /* don't follow CNAMEs, instead give _s_cname */
+  adns__qf_internalmask=   0x0ff00000
+} adns_queryflags;
+
+typedef enum {
+  adns__rrt_typemask=  0x0ffff,
+  adns__qtf_deref=     0x10000, /* dereference domains and perhaps produce extra data */
+  adns__qtf_mail822=   0x20000, /* make mailboxes be in RFC822 rcpt field format */
+  
+  adns_r_none=               0,
+  
+  adns_r_a=                  1,
+  
+  adns_r_ns_raw=             2,
+  adns_r_ns=                    adns_r_ns_raw|adns__qtf_deref,
+  
+  adns_r_cname=              5,
+  
+  adns_r_soa_raw=            6,
+  adns_r_soa=                   adns_r_soa_raw|adns__qtf_mail822, 
+  
+  adns_r_ptr_raw=           12,
+  adns_r_ptr=                   adns_r_ptr_raw|adns__qtf_deref,
+  
+  adns_r_hinfo=             13,  
+  
+  adns_r_mx_raw=            15,
+  adns_r_mx=                    adns_r_mx_raw|adns__qtf_deref,
+  
+  adns_r_txt=               16,
+  
+  adns_r_rp_raw=            17,
+  adns_r_rp=                    adns_r_rp_raw|adns__qtf_mail822,
+
+  adns_r_addr=                  adns_r_a|adns__qtf_deref
+  
+} adns_rrtype;
+
+/*
+ * In queries without qf_quoteok_*, all domains must have standard
+ * legal syntax, or you get adns_s_querydomainvalid (if the query
+ * domain contains bad characters) or adns_s_answerdomaininvalid (if
+ * the answer contains bad characters).
+ * 
+ * In queries _with_ qf_quoteok_*, domains in the query or response
+ * may contain any characters, quoted according to RFC1035 5.1.  On
+ * input to adns, the char* is a pointer to the interior of a "
+ * delimited string, except that " may appear in it, and on output,
+ * the char* is a pointer to a string which would be legal either
+ * inside or outside " delimiters, and any characters not usually
+ * legal in domain names will be quoted as \X (if the character is
+ * 33-126 except \ and ") or \DDD.
+ *
+ * If the query goes via a CNAME then the canonical name (ie, the
+ * thing that the CNAME record refers to) is usually allowed to
+ * contain any characters, which will be quoted as above.  With
+ * adns_qf_quotefail_cname you get adns_s_answerdomaininvalid when
+ * this happens.  (This is a change from version 0.4 and earlier, in
+ * which failing the query was the default, and you had to say
+ * adns_qf_quoteok_cname to avoid this; that flag is now deprecated.)
+ *
+ * In version 0.4 and earlier, asking for _raw records containing
+ * mailboxes without specifying _qf_quoteok_anshost was silly.  This
+ * is no longer the case.  In this version only parts of responses
+ * that are actually supposed to be hostnames will be refused by
+ * default if quote-requiring characters are found.
+ */
+
+/*
+ * If you ask for an RR which contains domains which are actually
+ * encoded mailboxes, and don't ask for the _raw version, then adns
+ * returns the mailbox formatted suitably for an RFC822 recipient
+ * header field.  The particular format used is that if the mailbox
+ * requires quoting according to the rules in RFC822 then the
+ * local-part is quoted in double quotes, which end at the next
+ * unescaped double quote.  (\ is the escape char, and is doubled, and
+ * is used to escape only \ and ".)  Otherwise the local-part is
+ * presented as-is.  In any case this is followed by an @ and the
+ * domain.  The domain will not contain any characters not legal in
+ * hostnames.  adns will protect the application from local parts
+ * containing control characters - these appear to be legal according
+ * to RFC822 but are clearly a bad idea.
+ *
+ * If you ask for the domain with _raw then _no_ checking is done
+ * (even on the host part, regardless of adns_qf_quoteok_anshost), and
+ * you just get the domain name in master file format.
+ *
+ * If no mailbox is supplied the returned string will be `.' in either
+ * caswe.
+ */
+
+typedef enum {
+  adns_s_ok,
+
+  /* locally induced errors */
+  adns_s_nomemory,
+  adns_s_unknownrrtype,
+  adns_s_systemfail,
+
+  adns_s_max_localfail= 29,
+  
+  /* remotely induced errors, detected locally */
+  adns_s_timeout,
+  adns_s_allservfail,
+  adns_s_norecurse,
+  adns_s_invalidresponse,
+  adns_s_unknownformat,
+
+  adns_s_max_remotefail= 59,
+  
+  /* remotely induced errors, reported by remote server to us */
+  adns_s_rcodeservfail,
+  adns_s_rcodeformaterror,
+  adns_s_rcodenotimplemented,
+  adns_s_rcoderefused,
+  adns_s_rcodeunknown,
+
+  adns_s_max_tempfail= 99,
+
+  /* remote configuration errors */
+  adns_s_inconsistent, /* PTR gives domain whose A does not exist and match */
+  adns_s_prohibitedcname, /* CNAME found where eg A expected (not if _qf_loosecname) */
+  adns_s_answerdomaininvalid,
+  adns_s_answerdomaintoolong,
+  adns_s_invaliddata,
+  
+  adns_s_max_misconfig= 199,
+
+  /* permanent problems with the query */
+  adns_s_querydomainwrong,
+  adns_s_querydomaininvalid,
+  adns_s_querydomaintoolong,
+  
+  adns_s_max_misquery= 299,
+
+  /* permanent errors */
+  adns_s_nxdomain,
+  adns_s_nodata,
+
+  adns_s_max_permfail= 499
+  
+} adns_status;
+
+typedef struct {
+  int len;
+  union {
+    struct sockaddr sa;
+    struct sockaddr_in inet;
+  } addr;
+} adns_rr_addr;
+
+typedef struct {
+  char *host;
+  adns_status astatus;
+  int naddrs; /* temp fail => -1, perm fail => 0, s_ok => >0 */
+  adns_rr_addr *addrs;
+} adns_rr_hostaddr;
+
+typedef struct {
+  char *(array[2]);
+} adns_rr_strpair;
+
+typedef struct {
+  int i;
+  adns_rr_hostaddr ha;
+} adns_rr_inthostaddr;
+
+typedef struct {
+  /* Used both for mx_raw, in which case i is the preference and str the domain,
+   * and for txt, in which case each entry has i for the `text' length,
+   * and str for the data (which will have had an extra nul appended
+   * so that if it was plain text it is now a null-terminated string).
+   */
+  int i;
+  char *str;
+} adns_rr_intstr;
+
+typedef struct {
+  adns_rr_intstr array[2];
+} adns_rr_intstrpair;
+
+typedef struct {
+  char *mname, *rname;
+  unsigned long serial, refresh, retry, expire, minimum;
+} adns_rr_soa;
+
+typedef struct {
+  adns_status status;
+  char *cname; /* always NULL if query was for CNAME records */
+  char *owner; /* only set if requested in query flags */
+  adns_rrtype type; /* guaranteed to be same as in query */
+  time_t expires; /* expiry time, defined only if _s_ok, nxdomain or nodata. NOT TTL! */
+  int nrrs, rrsz; /* nrrs is 0 if an error occurs */
+  union {
+    void *untyped;
+    unsigned char *bytes;
+    char *(*str);                     /* ns_raw, cname, ptr, ptr_raw */
+    adns_rr_intstr *(*manyistr);      /* txt (list of strings ends with i=-1, str=0) */
+    adns_rr_addr *addr;               /* addr */
+    struct in_addr *inaddr;           /* a */
+    adns_rr_hostaddr *hostaddr;       /* ns */
+    adns_rr_intstrpair *intstrpair;   /* hinfo */
+    adns_rr_strpair *strpair;         /* rp, rp_raw */
+    adns_rr_inthostaddr *inthostaddr; /* mx */
+    adns_rr_intstr *intstr;           /* mx_raw */
+    adns_rr_soa *soa;                 /* soa, soa_raw */
+  } rrs;
+} adns_answer;
+
+/* Memory management:
+ *  adns_state and adns_query are actually pointers to malloc'd state;
+ *  On submission questions are copied, including the owner domain;
+ *  Answers are malloc'd as a single piece of memory; pointers in the
+ *  answer struct point into further memory in the answer.
+ * query_io:
+ *  Must always be non-null pointer;
+ *  If *query_io is 0 to start with then any query may be returned;
+ *  If *query_io is !0 adns_query then only that query may be returned.
+ *  If the call is successful, *query_io, *answer_r, and *context_r
+ *  will all be set.
+ * Errors:
+ *  Return values are 0 or an errno value.
+ *
+ *  For _init, _init_strcfg, _submit and _synchronous, system errors
+ *  (eg, failure to create sockets, malloc failure, etc.) return errno
+ *  values.
+ * 
+ *  For _wait and _check failures are reported in the answer
+ *  structure, and only 0, ESRCH or (for _check) EAGAIN is
+ *  returned: if no (appropriate) requests are done adns_check returns
+ *  EAGAIN; if no (appropriate) requests are outstanding both
+ *  adns_query and adns_wait return ESRCH.
+ *
+ *  Additionally, _wait can return EINTR if you set adns_if_eintr.
+ *
+ *  All other errors (nameserver failure, timed out connections, &c)
+ *  are returned in the status field of the answer.  After a
+ *  successful _wait or _check, if status is nonzero then nrrs will be
+ *  0, otherwise it will be >0.  type will always be the type
+ *  requested.
+ */
+
+int adns_init(adns_state *newstate_r, adns_initflags flags,
+	      FILE *diagfile /*0=>stderr*/);
+
+int adns_init_strcfg(adns_state *newstate_r, adns_initflags flags,
+		     FILE *diagfile /*0=>discard*/, const char *configtext);
+
+/* Configuration:
+ *  adns_init reads /etc/resolv.conf, which is expected to be (broadly
+ *  speaking) in the format expected by libresolv, and then
+ *  /etc/resolv-adns.conf if it exists.  adns_init_strcfg is instead
+ *  passed a string which is interpreted as if it were the contents of
+ *  resolv.conf or resolv-adns.conf.  In general, configuration which
+ *  is set later overrides any that is set earlier.
+ *
+ * Standard directives understood in resolv[-adns].conf:
+ * 
+ *  nameserver <address>
+ *   Must be followed by the IP address of a nameserver.  Several
+ *   nameservers may be specified, and they will be tried in the order
+ *   found.  There is a compiled in limit, currently 5, on the number
+ *   of nameservers.  (libresolv supports only 3 nameservers.)
+ *
+ *  search <domain> ...
+ *   Specifies the search list for queries which specify
+ *   adns_qf_search.  This is a list of domains to append to the query
+ *   domain.  The query domain will be tried as-is either before all
+ *   of these or after them, depending on the ndots option setting
+ *   (see below).
+ *
+ *  domain <domain>
+ *   This is present only for backward compatibility with obsolete
+ *   versions of libresolv.  It should not be used, and is interpreted
+ *   by adns as if it were `search' - note that this is subtly
+ *   different to libresolv's interpretation of this directive.
+ *
+ *  sortlist <addr>/<mask> ...
+ *   Should be followed by a sequence of IP-address and netmask pairs,
+ *   separated by spaces.  They may be specified as
+ *   eg. 172.30.206.0/24 or 172.30.206.0/255.255.255.0.  Currently up
+ *   to 15 pairs may be specified (but note that libresolv only
+ *   supports up to 10).
+ *
+ *  options
+ *   Should followed by one or more options, separated by spaces.
+ *   Each option consists of an option name, followed by optionally
+ *   a colon and a value.  Options are listed below.
+ *
+ * Non-standard directives understood in resolv[-adns].conf:
+ *
+ *  clearnameservers
+ *   Clears the list of nameservers, so that further nameserver lines
+ *   start again from the beginning.
+ *
+ *  include <filename>
+ *   The specified file will be read.
+ *
+ * Additionally, adns will ignore lines in resolv[-adns].conf which
+ * start with a #.
+ *
+ * Standard options understood:
+ *
+ *  debug
+ *   Enables debugging output from the resolver, which will be written
+ *   to stderr.
+ *
+ *  ndots:<count>
+ *   Affects whether queries with adns_qf_search will be tried first
+ *   without adding domains from the searchlist, or whether the bare
+ *   query domain will be tried last.  Queries which contain at least
+ *   <count> dots will be tried bare first.  The default is 1.
+ *
+ * Non-standard options understood:
+ *
+ *  adns_checkc:none
+ *  adns_checkc:entex
+ *  adns_checkc:freq
+ *   Changes the consistency checking frequency; this overrides the
+ *   setting of adns_if_check_entex, adns_if_check_freq, or neither,
+ *   in the flags passed to adns_init.
+ * 
+ * There are a number of environment variables which can modify the
+ * behaviour of adns.  They take effect only if adns_init is used, and
+ * the caller of adns_init can disable them using adns_if_noenv.  In
+ * each case there is both a FOO and an ADNS_FOO; the latter is
+ * interpreted later so that it can override the former.  Unless
+ * otherwise stated, environment variables are interpreted after
+ * resolv[-adns].conf are read, in the order they are listed here.
+ *
+ *  RES_CONF, ADNS_RES_CONF
+ *   A filename, whose contets are in the format of resolv.conf.
+ *
+ *  RES_CONF_TEXT, ADNS_RES_CONF_TEXT
+ *   A string in the format of resolv.conf.
+ *
+ *  RES_OPTIONS, ADNS_RES_OPTIONS
+ *   These are parsed as if they appeared in the `options' line of a
+ *   resolv.conf.  In addition to being parsed at this point in the
+ *   sequence, they are also parsed at the very beginning before
+ *   resolv.conf or any other environment variables are read, so that
+ *   any debug option can affect the processing of the configuration.
+ *
+ *  LOCALDOMAIN, ADNS_LOCALDOMAIN
+ *   These are interpreted as if their contents appeared in a `search'
+ *   line in resolv.conf.
+ */
+
+int adns_synchronous(adns_state ads,
+		     const char *owner,
+		     adns_rrtype type,
+		     adns_queryflags flags,
+		     adns_answer **answer_r);
+
+/* NB: if you set adns_if_noautosys then _submit and _check do not
+ * make any system calls; you must use some of the asynch-io event
+ * processing functions to actually get things to happen.
+ */
+
+int adns_submit(adns_state ads,
+		const char *owner,
+		adns_rrtype type,
+		adns_queryflags flags,
+		void *context,
+		adns_query *query_r);
+
+/* The owner should be quoted in master file format. */
+
+int adns_check(adns_state ads,
+	       adns_query *query_io,
+	       adns_answer **answer_r,
+	       void **context_r);
+
+int adns_wait(adns_state ads,
+	      adns_query *query_io,
+	      adns_answer **answer_r,
+	      void **context_r);
+
+/* same as adns_wait but uses poll(2) internally */
+int adns_wait_poll(adns_state ads,
+		   adns_query *query_io,
+		   adns_answer **answer_r,
+		   void **context_r);
+
+void adns_cancel(adns_query query);
+
+/* The adns_query you get back from _submit is valid (ie, can be
+ * legitimately passed into adns functions) until it is returned by
+ * adns_check or adns_wait, or passed to adns_cancel.  After that it
+ * must not be used.  You can rely on it not being reused until the
+ * first adns_submit or _transact call using the same adns_state after
+ * it became invalid, so you may compare it for equality with other
+ * query handles until you next call _query or _transact.
+ *
+ * _submit and _synchronous return ENOSYS if they don't understand the
+ * query type.
+ */
+
+int adns_submit_reverse(adns_state ads,
+			const struct sockaddr *addr,
+			adns_rrtype type,
+			adns_queryflags flags,
+			void *context,
+			adns_query *query_r);
+/* type must be _r_ptr or _r_ptr_raw.  _qf_search is ignored.
+ * addr->sa_family must be AF_INET or you get ENOSYS.
+ */
+
+void adns_finish(adns_state ads);
+/* You may call this even if you have queries outstanding;
+ * they will be cancelled.
+ */
+
+
+void adns_forallqueries_begin(adns_state ads);
+adns_query adns_forallqueries_next(adns_state ads, void **context_r);
+/* Iterator functions, which you can use to loop over the outstanding
+ * (submitted but not yet successfuly checked/waited) queries.
+ *
+ * You can only have one iteration going at once.  You may call _begin
+ * at any time; after that, an iteration will be in progress.  You may
+ * only call _next when an iteration is in progress - anything else
+ * may coredump.  The iteration remains in progress until _next
+ * returns 0, indicating that all the queries have been walked over,
+ * or ANY other adns function is called with the same adns_state (or a
+ * query in the same adns_state).  There is no need to explicitly
+ * finish an iteration.
+ *
+ * context_r may be 0.  *context_r may not be set when _next returns 0.
+ */
+
+void adns_checkconsistency(adns_state ads, adns_query qu);
+/* Checks the consistency of adns's internal data structures.
+ * If any error is found, the program will abort().
+ * You may pass 0 for qu; if you pass non-null then additional checks
+ * are done to make sure that qu is a valid query.
+ */
+
+/*
+ * Example expected/legal calling sequence for submit/check/wait:
+ *  adns_init
+ *  adns_submit 1
+ *  adns_submit 2
+ *  adns_submit 3
+ *  adns_wait 1
+ *  adns_check 3 -> EAGAIN
+ *  adns_wait 2
+ *  adns_wait 3
+ *  ....
+ *  adns_finish
+ */
+
+/*
+ * Entrypoints for generic asynch io:
+ * (these entrypoints are not very useful except in combination with *
+ * some of the other I/O model calls which can tell you which fds to
+ * be interested in):
+ *
+ * Note that any adns call may cause adns to open and close fds, so
+ * you must call beforeselect or beforepoll again just before
+ * blocking, or you may not have an up-to-date list of it's fds.
+ */
+
+int adns_processany(adns_state ads);
+/* Gives adns flow-of-control for a bit.  This will never block, and
+ * can be used with any threading/asynch-io model.  If some error
+ * occurred which might cause an event loop to spin then the errno
+ * value is returned.
+ */
+
+int adns_processreadable(adns_state ads, int fd, const struct timeval *now);
+int adns_processwriteable(adns_state ads, int fd, const struct timeval *now);
+int adns_processexceptional(adns_state ads, int fd, const struct timeval *now);
+/* Gives adns flow-of-control so that it can process incoming data
+ * from, or send outgoing data via, fd.  Very like _processany.  If it
+ * returns zero then fd will no longer be readable or writeable
+ * (unless of course more data has arrived since).  adns will _only_
+ * use that fd and only in the manner specified, regardless of whether
+ * adns_if_noautosys was specified.
+ *
+ * adns_processexceptional should be called when select(2) reports an
+ * exceptional condition, or poll(2) reports POLLPRI.
+ *
+ * It is fine to call _processreabable or _processwriteable when the
+ * fd is not ready, or with an fd that doesn't belong to adns; it will
+ * then just return 0.
+ *
+ * If some error occurred which might prevent an event loop to spin
+ * then the errno value is returned.
+ */
+
+void adns_processtimeouts(adns_state ads, const struct timeval *now);
+/* Gives adns flow-of-control so that it can process any timeouts
+ * which might have happened.  Very like _processreadable/writeable.
+ *
+ * now may be 0; if it isn't, *now must be the current time, recently
+ * obtained from gettimeofday.
+ */
+
+void adns_firsttimeout(adns_state ads,
+		       struct timeval **tv_mod, struct timeval *tv_buf,
+		       struct timeval now);
+/* Asks adns when it would first like the opportunity to time
+ * something out.  now must be the current time, from gettimeofday.
+ * 
+ * If tv_mod points to 0 then tv_buf must be non-null, and
+ * _firsttimeout will fill in *tv_buf with the time until the first
+ * timeout, and make *tv_mod point to tv_buf.  If adns doesn't have
+ * anything that might need timing out it will leave *tv_mod as 0.
+ *
+ * If *tv_mod is not 0 then tv_buf is not used.  adns will update
+ * *tv_mod if it has any earlier timeout, and leave it alone if it
+ * doesn't.
+ *
+ * This call will not actually do any I/O, or change the fds that adns
+ * is using.  It always succeeds and never blocks.
+ */
+
+void adns_globalsystemfailure(adns_state ads);
+/* If serious problem(s) happen which globally affect your ability to
+ * interact properly with adns, or adns's ability to function
+ * properly, you or adns can call this function.
+ *
+ * All currently outstanding queries will be made to fail with
+ * adns_s_systemfail, and adns will close any stream sockets it has
+ * open.
+ *
+ * This is used by adns, for example, if gettimeofday() fails.
+ * Without this the program's event loop might start to spin !
+ *
+ * This call will never block.
+ */
+
+/*
+ * Entrypoints for select-loop based asynch io:
+ */
+
+void adns_beforeselect(adns_state ads, int *maxfd, fd_set *readfds,
+		       fd_set *writefds, fd_set *exceptfds,
+		       struct timeval **tv_mod, struct timeval *tv_buf,
+		       const struct timeval *now);
+/* Find out file descriptors adns is interested in, and when it would
+ * like the opportunity to time something out.  If you do not plan to
+ * block then tv_mod may be 0.  Otherwise, tv_mod and tv_buf are as
+ * for adns_firsttimeout.  readfds, writefds, exceptfds and maxfd_io may
+ * not be 0.
+ *
+ * If *now is not 0 then this will never actually do any I/O, or
+ * change the fds that adns is using or the timeouts it wants.  In any
+ * case it won't block.
+ */
+
+void adns_afterselect(adns_state ads, int maxfd, const fd_set *readfds,
+		      const fd_set *writefds, const fd_set *exceptfds,
+		      const struct timeval *now);
+/* Gives adns flow-of-control for a bit; intended for use after
+ * select.  This is just a fancy way of calling adns_processreadable/
+ * writeable/timeouts as appropriate, as if select had returned the
+ * data being passed.  Always succeeds.
+ */
+
+/*
+ * Example calling sequence:
+ *
+ *  adns_init _noautosys
+ *  loop {
+ *   adns_beforeselect
+ *   select
+ *   adns_afterselect
+ *   ...
+ *   adns_submit / adns_check
+ *   ...
+ *  }
+ */
+
+/*
+ * Entrypoints for poll-loop based asynch io:
+ */
+
+struct pollfd;
+/* In case your system doesn't have it or you forgot to include
+ * <sys/poll.h>, to stop the following declarations from causing
+ * problems.  If your system doesn't have poll then the following
+ * entrypoints will not be defined in libadns.  Sorry !
+ */
+
+int adns_beforepoll(adns_state ads, struct pollfd *fds, int *nfds_io, int *timeout_io,
+		    const struct timeval *now);
+/* Finds out which fd's adns is interested in, and when it would like
+ * to be able to time things out.  This is in a form suitable for use
+ * with poll(2).
+ * 
+ * On entry, usually fds should point to at least *nfds_io structs.
+ * adns will fill up to that many structs will information for poll,
+ * and record in *nfds_io how many structs it filled.  If it wants to
+ * listen for more structs then *nfds_io will be set to the number
+ * required and _beforepoll will return ERANGE.
+ *
+ * You may call _beforepoll with fds==0 and *nfds_io 0, in which case
+ * adns will fill in the number of fds that it might be interested in
+ * in *nfds_io, and always return either 0 (if it is not interested in
+ * any fds) or ERANGE (if it is).
+ *
+ * NOTE that (unless now is 0) adns may acquire additional fds
+ * from one call to the next, so you must put adns_beforepoll in a
+ * loop, rather than assuming that the second call (with the buffer
+ * size requested by the first) will not return ERANGE.
+ *
+ * adns only ever sets POLLIN, POLLOUT and POLLPRI in its pollfd
+ * structs, and only ever looks at those bits.  POLLPRI is required to
+ * detect TCP Urgent Data (which should not be used by a DNS server)
+ * so that adns can know that the TCP stream is now useless.
+ *
+ * In any case, *timeout_io should be a timeout value as for poll(2),
+ * which adns will modify downwards as required.  If the caller does
+ * not plan to block then *timeout_io should be 0 on entry, or
+ * alternatively, timeout_io may be 0.  (Alternatively, the caller may
+ * use _beforeselect with timeout_io==0 to find out about file
+ * descriptors, and use _firsttimeout is used to find out when adns
+ * might want to time something out.)
+ *
+ * adns_beforepoll will return 0 on success, and will not fail for any
+ * reason other than the fds buffer being too small (ERANGE).
+ *
+ * This call will never actually do any I/O.  If you supply the
+ * current time it will not change the fds that adns is using or the
+ * timeouts it wants.
+ *
+ * In any case this call won't block.
+ */
+
+#define ADNS_POLLFDS_RECOMMENDED 2
+/* If you allocate an fds buf with at least RECOMMENDED entries then
+ * you are unlikely to need to enlarge it.  You are recommended to do
+ * so if it's convenient.  However, you must be prepared for adns to
+ * require more space than this.
+ */
+
+void adns_afterpoll(adns_state ads, const struct pollfd *fds, int nfds,
+		    const struct timeval *now);
+/* Gives adns flow-of-control for a bit; intended for use after
+ * poll(2).  fds and nfds should be the results from poll().  pollfd
+ * structs mentioning fds not belonging to adns will be ignored.
+ */
+
+
+adns_status adns_rr_info(adns_rrtype type,
+			 const char **rrtname_r, const char **fmtname_r,
+			 int *len_r,
+			 const void *datap, char **data_r);
+/*
+ * Get information about a query type, or convert reply data to a
+ * textual form.  type must be specified, and the official name of the
+ * corresponding RR type will be returned in *rrtname_r, and
+ * information about the processing style in *fmtname_r.  The length
+ * of the table entry in an answer for that type will be returned in
+ * in *len_r.  Any or all of rrtname_r, fmtname_r and len_r may be 0.
+ * If fmtname_r is non-null then *fmtname_r may be null on return,
+ * indicating that no special processing is involved.
+ *
+ * data_r be must be non-null iff datap is.  In this case *data_r will
+ * be set to point to a string pointing to a representation of the RR
+ * data in master file format.  (The owner name, timeout, class and
+ * type will not be present - only the data part of the RR.)  The
+ * memory will have been obtained from malloc() and must be freed by
+ * the caller.
+ *
+ * Usually this routine will succeed.  Possible errors include:
+ *  adns_s_nomemory
+ *  adns_s_rrtypeunknown
+ *  adns_s_invaliddata (*datap contained garbage)
+ * If an error occurs then no memory has been allocated,
+ * and *rrtname_r, *fmtname_r, *len_r and *data_r are undefined.
+ *
+ * There are some adns-invented data formats which are not official
+ * master file formats.  These include:
+ *
+ * Mailboxes if __qtf_mail822: these are just included as-is.
+ *
+ * Addresses (adns_rr_addr): these may be of pretty much any type.
+ * The representation is in two parts: first, a word for the address
+ * family (ie, in AF_XXX, the XXX), and then one or more items for the
+ * address itself, depending on the format.  For an IPv4 address the
+ * syntax is INET followed by the dotted quad (from inet_ntoa).
+ * Currently only IPv4 is supported.
+ *
+ * Text strings (as in adns_rr_txt) appear inside double quotes, and
+ * use \" and \\ to represent " and \, and \xHH to represent
+ * characters not in the range 32-126.
+ *
+ * Hostname with addresses (adns_rr_hostaddr): this consists of the
+ * hostname, as usual, followed by the adns_status value, as an
+ * abbreviation, and then a descriptive string (encoded as if it were
+ * a piece of text), for the address lookup, followed by zero or more
+ * addresses enclosed in ( and ).  If the result was a permanent
+ * failure, then a single ?  appears instead of the ( ).  If the
+ * result was a temporary failure then an empty pair of parentheses
+ * appears (which a space in between).  For example, one of the NS
+ * records for greenend.org.uk comes out like
+ *  ns.chiark.greenend.org.uk ok "OK" ( INET 195.224.76.132 )
+ * an MX referring to a nonexistent host might come out like:
+ *  50 sun2.nsfnet-relay.ac.uk nxdomain "No such domain" ( )
+ * and if nameserver information is not available you might get:
+ *  dns2.spong.dyn.ml.org timeout "DNS query timed out" ?
+ */
+
+const char *adns_strerror(adns_status st);
+const char *adns_errabbrev(adns_status st);
+const char *adns_errtypeabbrev(adns_status st);
+/* Like strerror but for adns_status values.  adns_errabbrev returns
+ * the abbreviation of the error - eg, for adns_s_timeout it returns
+ * "timeout".  adns_errtypeabbrev returns the abbreviation of the
+ * error class: ie, for values up to adns_s_max_XXX it will return the
+ * string XXX.  You MUST NOT call these functions with status values
+ * not returned by the same adns library.
+ */
+
+#ifdef __cplusplus
+} /* end of extern "C" */
+#endif
+#endif