.TH "event2/dns_compat.h" 3 "Tue Jan 31 2017" "libevent" \" -*- nroff -*-
.ad l
.nh
.SH NAME
event2/dns_compat.h \- Potentially non-threadsafe versions of the functions in \fBdns\&.h\fP: provided only for backwards compatibility\&.  

.SH SYNOPSIS
.br
.PP
\fC#include <event2/event\-config\&.h>\fP
.br
\fC#include <event2/util\&.h>\fP
.br

.SS "Functions"

.in +1c
.ti -1c
.RI "struct evdns_server_port * \fBevdns_add_server_port\fP (\fBevutil_socket_t\fP socket, int flags, \fBevdns_request_callback_fn_type\fP callback, void *user_data)"
.br
.RI "\fIAs evdns_server_new_with_base\&. \fP"
.ti -1c
.RI "int \fBevdns_clear_nameservers_and_suspend\fP (void)"
.br
.RI "\fIRemove all configured nameservers, and suspend all pending resolves\&. \fP"
.ti -1c
.RI "int \fBevdns_count_nameservers\fP (void)"
.br
.RI "\fIGet the number of configured nameservers\&. \fP"
.ti -1c
.RI "struct evdns_base * \fBevdns_get_global_base\fP (void)"
.br
.RI "\fIReturn the global evdns_base created by \fBevent_init()\fP and used by the other deprecated functions\&. \fP"
.ti -1c
.RI "int \fBevdns_init\fP (void)"
.br
.RI "\fIInitialize the asynchronous DNS library\&. \fP"
.ti -1c
.RI "int \fBevdns_nameserver_add\fP (unsigned long int address)"
.br
.RI "\fIAdd a nameserver\&. \fP"
.ti -1c
.RI "int \fBevdns_nameserver_ip_add\fP (const char *ip_as_string)"
.br
.RI "\fIAdd a nameserver\&. \fP"
.ti -1c
.RI "int \fBevdns_resolv_conf_parse\fP (int flags, const char *const filename)"
.br
.RI "\fIParse a resolv\&.conf file\&. \fP"
.ti -1c
.RI "int \fBevdns_resolve_ipv4\fP (const char *name, int flags, \fBevdns_callback_type\fP callback, void *ptr)"
.br
.RI "\fILookup an A record for a given name\&. \fP"
.ti -1c
.RI "int \fBevdns_resolve_ipv6\fP (const char *name, int flags, \fBevdns_callback_type\fP callback, void *ptr)"
.br
.RI "\fILookup an AAAA record for a given name\&. \fP"
.ti -1c
.RI "int \fBevdns_resolve_reverse\fP (const struct in_addr *in, int flags, \fBevdns_callback_type\fP callback, void *ptr)"
.br
.RI "\fILookup a PTR record for a given IP address\&. \fP"
.ti -1c
.RI "int \fBevdns_resolve_reverse_ipv6\fP (const struct in6_addr *in, int flags, \fBevdns_callback_type\fP callback, void *ptr)"
.br
.RI "\fILookup a PTR record for a given IPv6 address\&. \fP"
.ti -1c
.RI "int \fBevdns_resume\fP (void)"
.br
.RI "\fIResume normal operation and continue any suspended resolve requests\&. \fP"
.ti -1c
.RI "void \fBevdns_search_add\fP (const char *domain)"
.br
.RI "\fIAdd a domain to the list of search domains\&. \fP"
.ti -1c
.RI "void \fBevdns_search_clear\fP (void)"
.br
.RI "\fIClear the list of search domains\&. \fP"
.ti -1c
.RI "void \fBevdns_search_ndots_set\fP (const int ndots)"
.br
.RI "\fISet the 'ndots' parameter for searches\&. \fP"
.ti -1c
.RI "int \fBevdns_set_option\fP (const char *option, const char *val, int flags)"
.br
.RI "\fISet the value of a configuration option\&. \fP"
.ti -1c
.RI "void \fBevdns_shutdown\fP (int fail_requests)"
.br
.RI "\fIShut down the asynchronous DNS resolver and terminate all active requests\&. \fP"
.in -1c
.SH "Detailed Description"
.PP 
Potentially non-threadsafe versions of the functions in \fBdns\&.h\fP: provided only for backwards compatibility\&. 


.SH "Function Documentation"
.PP 
.SS "struct evdns_server_port* evdns_add_server_port (\fBevutil_socket_t\fP socket, int flags, \fBevdns_request_callback_fn_type\fP callback, void * user_data)"

.PP
As evdns_server_new_with_base\&. 
.PP
\fBDeprecated\fP
.RS 4
This function is deprecated because it does not allow the caller to specify which even_base it uses\&. The recommended function is \fBevdns_add_server_port_with_base()\fP\&.
.RE
.PP

.SS "int evdns_clear_nameservers_and_suspend (void)"

.PP
Remove all configured nameservers, and suspend all pending resolves\&. Resolves will not necessarily be re-attempted until \fBevdns_resume()\fP is called\&.
.PP
\fBDeprecated\fP
.RS 4
This function is deprecated because it does not allow the caller to specify which evdns_base it applies to\&. The recommended function is \fBevdns_base_clear_nameservers_and_suspend()\fP\&.
.RE
.PP
.PP
\fBReturns:\fP
.RS 4
0 if successful, or -1 if an error occurred 
.RE
.PP
\fBSee also:\fP
.RS 4
\fBevdns_resume()\fP 
.RE
.PP

.SS "int evdns_count_nameservers (void)"

.PP
Get the number of configured nameservers\&. This returns the number of configured nameservers (not necessarily the number of running nameservers)\&. This is useful for double-checking whether our calls to the various nameserver configuration functions have been successful\&.
.PP
\fBDeprecated\fP
.RS 4
This function is deprecated because it does not allow the caller to specify which evdns_base it applies to\&. The recommended function is \fBevdns_base_count_nameservers()\fP\&.
.RE
.PP
.PP
\fBReturns:\fP
.RS 4
the number of configured nameservers 
.RE
.PP
\fBSee also:\fP
.RS 4
\fBevdns_nameserver_add()\fP 
.RE
.PP

.SS "struct evdns_base* evdns_get_global_base (void)"

.PP
Return the global evdns_base created by \fBevent_init()\fP and used by the other deprecated functions\&. 
.PP
\fBDeprecated\fP
.RS 4
This function is deprecated because use of the global evdns_base is error-prone\&. 
.RE
.PP

.SS "int evdns_init (void)"

.PP
Initialize the asynchronous DNS library\&. This function initializes support for non-blocking name resolution by calling \fBevdns_resolv_conf_parse()\fP on UNIX and evdns_config_windows_nameservers() on Windows\&.
.PP
\fBDeprecated\fP
.RS 4
This function is deprecated because it always uses the current event base, and is easily confused by multiple calls to \fBevent_init()\fP, and so is not safe for multithreaded use\&. Additionally, it allocates a global structure that only one thread can use\&. The replacement is \fBevdns_base_new()\fP\&.
.RE
.PP
.PP
\fBReturns:\fP
.RS 4
0 if successful, or -1 if an error occurred 
.RE
.PP
\fBSee also:\fP
.RS 4
\fBevdns_shutdown()\fP 
.RE
.PP

.SS "int evdns_nameserver_add (unsigned long int address)"

.PP
Add a nameserver\&. The address should be an IPv4 address in network byte order\&. The type of address is chosen so that it matches in_addr\&.s_addr\&.
.PP
\fBDeprecated\fP
.RS 4
This function is deprecated because it does not allow the caller to specify which evdns_base it applies to\&. The recommended function is \fBevdns_base_nameserver_add()\fP\&.
.RE
.PP
.PP
\fBParameters:\fP
.RS 4
\fIaddress\fP an IP address in network byte order 
.RE
.PP
\fBReturns:\fP
.RS 4
0 if successful, or -1 if an error occurred 
.RE
.PP
\fBSee also:\fP
.RS 4
\fBevdns_nameserver_ip_add()\fP 
.RE
.PP

.SS "int evdns_nameserver_ip_add (const char * ip_as_string)"

.PP
Add a nameserver\&. This wraps the \fBevdns_nameserver_add()\fP function by parsing a string as an IP address and adds it as a nameserver\&.
.PP
\fBDeprecated\fP
.RS 4
This function is deprecated because it does not allow the caller to specify which evdns_base it applies to\&. The recommended function is \fBevdns_base_nameserver_ip_add()\fP\&.
.RE
.PP
.PP
\fBReturns:\fP
.RS 4
0 if successful, or -1 if an error occurred 
.RE
.PP
\fBSee also:\fP
.RS 4
\fBevdns_nameserver_add()\fP 
.RE
.PP

.SS "int evdns_resolv_conf_parse (int flags, const char *const filename)"

.PP
Parse a resolv\&.conf file\&. The 'flags' parameter determines what information is parsed from the resolv\&.conf file\&. See the man page for resolv\&.conf for the format of this file\&.
.PP
The following directives are not parsed from the file: sortlist, rotate, no-check-names, inet6, debug\&.
.PP
If this function encounters an error, the possible return values are: 1 = failed to open file, 2 = failed to stat file, 3 = file too large, 4 = out of memory, 5 = short read from file, 6 = no nameservers listed in the file
.PP
\fBDeprecated\fP
.RS 4
This function is deprecated because it does not allow the caller to specify which evdns_base it applies to\&. The recommended function is \fBevdns_base_resolv_conf_parse()\fP\&.
.RE
.PP
.PP
\fBParameters:\fP
.RS 4
\fIflags\fP any of DNS_OPTION_NAMESERVERS|DNS_OPTION_SEARCH|DNS_OPTION_MISC| DNS_OPTIONS_ALL 
.br
\fIfilename\fP the path to the resolv\&.conf file 
.RE
.PP
\fBReturns:\fP
.RS 4
0 if successful, or various positive error codes if an error occurred (see above) 
.RE
.PP
\fBSee also:\fP
.RS 4
resolv\&.conf(3), evdns_config_windows_nameservers() 
.RE
.PP

.SS "int evdns_resolve_ipv4 (const char * name, int flags, \fBevdns_callback_type\fP callback, void * ptr)"

.PP
Lookup an A record for a given name\&. 
.PP
\fBDeprecated\fP
.RS 4
This function is deprecated because it does not allow the caller to specify which evdns_base it applies to\&. The recommended function is \fBevdns_base_resolve_ipv4()\fP\&.
.RE
.PP
.PP
\fBParameters:\fP
.RS 4
\fIname\fP a DNS hostname 
.br
\fIflags\fP either 0, or DNS_QUERY_NO_SEARCH to disable searching for this query\&. 
.br
\fIcallback\fP a callback function to invoke when the request is completed 
.br
\fIptr\fP an argument to pass to the callback function 
.RE
.PP
\fBReturns:\fP
.RS 4
0 if successful, or -1 if an error occurred 
.RE
.PP
\fBSee also:\fP
.RS 4
\fBevdns_resolve_ipv6()\fP, \fBevdns_resolve_reverse()\fP, \fBevdns_resolve_reverse_ipv6()\fP 
.RE
.PP

.SS "int evdns_resolve_ipv6 (const char * name, int flags, \fBevdns_callback_type\fP callback, void * ptr)"

.PP
Lookup an AAAA record for a given name\&. 
.PP
\fBParameters:\fP
.RS 4
\fIname\fP a DNS hostname 
.br
\fIflags\fP either 0, or DNS_QUERY_NO_SEARCH to disable searching for this query\&. 
.br
\fIcallback\fP a callback function to invoke when the request is completed 
.br
\fIptr\fP an argument to pass to the callback function 
.RE
.PP
\fBReturns:\fP
.RS 4
0 if successful, or -1 if an error occurred 
.RE
.PP
\fBSee also:\fP
.RS 4
\fBevdns_resolve_ipv4()\fP, \fBevdns_resolve_reverse()\fP, \fBevdns_resolve_reverse_ipv6()\fP 
.RE
.PP

.SS "int evdns_resolve_reverse (const struct in_addr * in, int flags, \fBevdns_callback_type\fP callback, void * ptr)"

.PP
Lookup a PTR record for a given IP address\&. 
.PP
\fBDeprecated\fP
.RS 4
This function is deprecated because it does not allow the caller to specify which evdns_base it applies to\&. The recommended function is \fBevdns_base_resolve_reverse()\fP\&.
.RE
.PP
.PP
\fBParameters:\fP
.RS 4
\fIin\fP an IPv4 address 
.br
\fIflags\fP either 0, or DNS_QUERY_NO_SEARCH to disable searching for this query\&. 
.br
\fIcallback\fP a callback function to invoke when the request is completed 
.br
\fIptr\fP an argument to pass to the callback function 
.RE
.PP
\fBReturns:\fP
.RS 4
0 if successful, or -1 if an error occurred 
.RE
.PP
\fBSee also:\fP
.RS 4
\fBevdns_resolve_reverse_ipv6()\fP 
.RE
.PP

.SS "int evdns_resolve_reverse_ipv6 (const struct in6_addr * in, int flags, \fBevdns_callback_type\fP callback, void * ptr)"

.PP
Lookup a PTR record for a given IPv6 address\&. 
.PP
\fBDeprecated\fP
.RS 4
This function is deprecated because it does not allow the caller to specify which evdns_base it applies to\&. The recommended function is \fBevdns_base_resolve_reverse_ipv6()\fP\&.
.RE
.PP
.PP
\fBParameters:\fP
.RS 4
\fIin\fP an IPv6 address 
.br
\fIflags\fP either 0, or DNS_QUERY_NO_SEARCH to disable searching for this query\&. 
.br
\fIcallback\fP a callback function to invoke when the request is completed 
.br
\fIptr\fP an argument to pass to the callback function 
.RE
.PP
\fBReturns:\fP
.RS 4
0 if successful, or -1 if an error occurred 
.RE
.PP
\fBSee also:\fP
.RS 4
\fBevdns_resolve_reverse_ipv6()\fP 
.RE
.PP

.SS "int evdns_resume (void)"

.PP
Resume normal operation and continue any suspended resolve requests\&. Re-attempt resolves left in limbo after an earlier call to \fBevdns_clear_nameservers_and_suspend()\fP\&.
.PP
\fBDeprecated\fP
.RS 4
This function is deprecated because it does not allow the caller to specify which evdns_base it applies to\&. The recommended function is \fBevdns_base_resume()\fP\&.
.RE
.PP
.PP
\fBReturns:\fP
.RS 4
0 if successful, or -1 if an error occurred 
.RE
.PP
\fBSee also:\fP
.RS 4
\fBevdns_clear_nameservers_and_suspend()\fP 
.RE
.PP

.SS "void evdns_search_add (const char * domain)"

.PP
Add a domain to the list of search domains\&. 
.PP
\fBDeprecated\fP
.RS 4
This function is deprecated because it does not allow the caller to specify which evdns_base it applies to\&. The recommended function is \fBevdns_base_search_add()\fP\&.
.RE
.PP
.PP
\fBParameters:\fP
.RS 4
\fIdomain\fP the domain to be added to the search list 
.RE
.PP

.SS "void evdns_search_clear (void)"

.PP
Clear the list of search domains\&. 
.PP
\fBDeprecated\fP
.RS 4
This function is deprecated because it does not allow the caller to specify which evdns_base it applies to\&. The recommended function is \fBevdns_base_search_clear()\fP\&. 
.RE
.PP

.SS "void evdns_search_ndots_set (const int ndots)"

.PP
Set the 'ndots' parameter for searches\&. Sets the number of dots which, when found in a name, causes the first query to be without any search domain\&.
.PP
\fBDeprecated\fP
.RS 4
This function is deprecated because it does not allow the caller to specify which evdns_base it applies to\&. The recommended function is \fBevdns_base_search_ndots_set()\fP\&.
.RE
.PP
.PP
\fBParameters:\fP
.RS 4
\fIndots\fP the new ndots parameter 
.RE
.PP

.SS "int evdns_set_option (const char * option, const char * val, int flags)"

.PP
Set the value of a configuration option\&. The currently available configuration options are:
.PP
ndots, timeout, max-timeouts, max-inflight, and attempts
.PP
\fBDeprecated\fP
.RS 4
This function is deprecated because it does not allow the caller to specify which evdns_base it applies to\&. The recommended function is \fBevdns_base_set_option()\fP\&.
.RE
.PP
.PP
\fBParameters:\fP
.RS 4
\fIoption\fP the name of the configuration option to be modified 
.br
\fIval\fP the value to be set 
.br
\fIflags\fP Ignored\&. 
.RE
.PP
\fBReturns:\fP
.RS 4
0 if successful, or -1 if an error occurred 
.RE
.PP

.SS "void evdns_shutdown (int fail_requests)"

.PP
Shut down the asynchronous DNS resolver and terminate all active requests\&. If the 'fail_requests' option is enabled, all active requests will return an empty result with the error flag set to DNS_ERR_SHUTDOWN\&. Otherwise, the requests will be silently discarded\&.
.PP
\fBDeprecated\fP
.RS 4
This function is deprecated because it does not allow the caller to specify which evdns_base it applies to\&. The recommended function is evdns_base_shutdown()\&.
.RE
.PP
.PP
\fBParameters:\fP
.RS 4
\fIfail_requests\fP if zero, active requests will be aborted; if non-zero, active requests will return DNS_ERR_SHUTDOWN\&. 
.RE
.PP
\fBSee also:\fP
.RS 4
\fBevdns_init()\fP 
.RE
.PP

.SH "Author"
.PP 
Generated automatically by Doxygen for libevent from the source code\&.