Annotation of embedaddon/curl/docs/libcurl/opts/CURLOPT_DNS_SHUFFLE_ADDRESSES.3, revision 1.1
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! 23: .TH CURLOPT_DNS_SHUFFLE_ADDRESSES 3 "March 17, 2018" "libcurl 7.70.0" "curl_easy_setopt options"
! 24:
! 25: .SH NAME
! 26: CURLOPT_DNS_SHUFFLE_ADDRESSES \- Shuffle addresses when a hostname returns more than one
! 27: .SH SYNOPSIS
! 28: .nf
! 29: #include <curl/curl.h>
! 30:
! 31: CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DNS_SHUFFLE_ADDRESSES, long onoff);
! 32: .fi
! 33: .SH DESCRIPTION
! 34: When a name is resolved and more than one IP address is returned, shuffle the
! 35: order of all returned addresses so that they will be used in a random order.
! 36: This is similar to the ordering behavior of gethostbyname which is no longer
! 37: used on most platforms.
! 38:
! 39: Addresses will not be reshuffled if a name resolution is completed using the
! 40: DNS cache. \fICURLOPT_DNS_CACHE_TIMEOUT(3)\fP can be used together with this
! 41: option to reduce DNS cache timeout or disable caching entirely if frequent
! 42: reshuffling is needed.
! 43:
! 44: Since the addresses returned will be reordered randomly, their order will not
! 45: be in accordance with RFC 3484 or any other deterministic order that may be
! 46: generated by the system's name resolution implementation. This may have
! 47: performance impacts and may cause IPv4 to be used before IPv6 or vice versa.
! 48: .SH DEFAULT
! 49: 0 (disabled)
! 50: .SH PROTOCOLS
! 51: All
! 52: .SH EXAMPLE
! 53: .nf
! 54: CURL *curl = curl_easy_init();
! 55: if(curl) {
! 56: curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
! 57: curl_easy_setopt(curl, CURLOPT_DNS_SHUFFLE_ADDRESSES, 1L);
! 58:
! 59: curl_easy_perform(curl);
! 60:
! 61: /* always cleanup */
! 62: curl_easy_cleanup(curl);
! 63: }
! 64: .fi
! 65: .SH AVAILABILITY
! 66: Added in 7.60.0
! 67: .SH RETURN VALUE
! 68: CURLE_OK or an error such as CURLE_UNKNOWN_OPTION.
! 69: .SH "SEE ALSO"
! 70: .BR CURLOPT_DNS_CACHE_TIMEOUT "(3), " CURLOPT_IPRESOLVE "(3), "
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