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| .\" * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. |
| .\" * |
| .\" * This software is licensed as described in the file COPYING, which |
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| .\" |
| .TH CURLOPT_RESOLVE 3 "19 Jun 2014" libcurl libcurl |
| .SH NAME |
| CURLOPT_RESOLVE \- provide custom host name to IP address resolves |
| .SH SYNOPSIS |
| .nf |
| #include <curl/curl.h> |
| |
| CURLcode curl_easy_setopt(CURL *handle, CURLOPT_RESOLVE, |
| struct curl_slist *hosts); |
| .SH DESCRIPTION |
| Pass a pointer to a linked list of strings with host name resolve information |
| to use for requests with this handle. The linked list should be a fully valid |
| list of \fBstruct curl_slist\fP structs properly filled in. Use |
| \fIcurl_slist_append(3)\fP to create the list and \fIcurl_slist_free_all(3)\fP |
| to clean up an entire list. |
| |
| Each resolve rule to add should be written using the format |
| |
| .nf |
| [+]HOST:PORT:ADDRESS[,ADDRESS] |
| .fi |
| |
| HOST is the name libcurl wants to resolve, PORT is the port number of the |
| service where libcurl wants to connect to the HOST and ADDRESS is one or more |
| numerical IP addresses. If you specify multiple IP addresses they need to be |
| separated by comma. If libcurl is built to support IPv6, each of the ADDRESS |
| entries can of course be either IPv4 or IPv6 style addressing. |
| |
| This option effectively populates the DNS cache with entries for the host+port |
| pair so redirects and everything that operations against the HOST+PORT instead |
| use your provided ADDRESS. |
| |
| The optional leading "+" specifies that the new entry should time-out. Entries |
| added without the leading plus character never times out whereas entries added |
| with "+HOST:..." times out just like ordinary DNS cache entries. |
| |
| If the DNS cache already has an entry for the given host+port pair, the new |
| entry overrides the former one. |
| |
| An ADDRESS provided by this option is only used if not restricted by the |
| setting of \fICURLOPT_IPRESOLVE(3)\fP to a different IP version. |
| |
| To remove names from the DNS cache again, to stop providing these fake |
| resolves, include a string in the linked list that uses the format |
| |
| .nf |
| -HOST:PORT |
| .fi |
| |
| The entry to remove must be prefixed with a dash, and the host name and port |
| number must exactly match what was added previously. |
| .SH DEFAULT |
| NULL |
| .SH PROTOCOLS |
| All |
| .SH EXAMPLE |
| .nf |
| CURL *curl; |
| struct curl_slist *host = NULL; |
| host = curl_slist_append(NULL, "example.com:443:127.0.0.1"); |
| |
| curl = curl_easy_init(); |
| if(curl) { |
| curl_easy_setopt(curl, CURLOPT_RESOLVE, host); |
| curl_easy_setopt(curl, CURLOPT_URL, "https://example.com"); |
| |
| curl_easy_perform(curl); |
| |
| /* always cleanup */ |
| curl_easy_cleanup(curl); |
| } |
| |
| curl_slist_free_all(host); |
| .fi |
| .SH AVAILABILITY |
| Added in 7.21.3. Removal support added in 7.42.0. |
| |
| Support for providing the ADDRESS within [brackets] was added in 7.57.0. |
| |
| Support for providing multiple IP addresses per entry was added in 7.59.0. |
| |
| Support for adding non-permanent entries by using the "+" prefix was added in |
| 7.75.0. |
| .SH RETURN VALUE |
| Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not. |
| .SH "SEE ALSO" |
| .BR CURLOPT_CONNECT_TO (3), |
| .BR CURLOPT_DNS_CACHE_TIMEOUT (3), |
| .BR CURLOPT_IPRESOLVE (3) |
