curl/docs/libcurl/opts/CURLSHOPT_SHARE.3

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.TH CURLSHOPT_SHARE 3 "8 Aug 2003" "libcurl 7.10.7" "libcurl Manual"
.SH NAME
CURLSHOPT_SHARE - add data to share
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURLSHcode curl_share_setopt(CURLSH *share, CURLSHOPT_SHARE, long type);
.fi
.SH DESCRIPTION
The \fItype\fP parameter specifies what specific data that should be shared
and kept in the share object that was created with \fIcurl_share_init(3)\fP.
The given \fItype\fP must be be one of the values described below. You can set
\fICURLSHOPT_SHARE(3)\fP multiple times with different data arguments to have
the share object share multiple types of data. Unset a type again by setting
\fICURLSHOPT_UNSHARE(3)\fP.
.IP CURL_LOCK_DATA_COOKIE
Cookie data will be shared across the easy handles using this shared object.
Note that this does not activate an easy handle's cookie handling. You can do
that separately by using \fICURLOPT_COOKIEFILE(3)\fP for example.
.IP CURL_LOCK_DATA_DNS
Cached DNS hosts will be shared across the easy handles using this shared
object. Note that when you use the multi interface, all easy handles added to
the same multi handle will share DNS cache by default without using this
option.
.IP CURL_LOCK_DATA_SSL_SESSION
SSL session IDs will be shared across the easy handles using this shared
object. This will reduce the time spent in the SSL handshake when reconnecting
to the same server. Note SSL session IDs are reused within the same easy
handle by default. Note this symbol was added in 7.10.3 but was not
implemented until 7.23.0.
.IP CURL_LOCK_DATA_CONNECT
Put the connection cache in the share object and make all easy handles using
this share object share the connection cache.

Note that due to a known bug, it is not safe to share connections this way
between multiple concurrent threads.

Connections that are used for HTTP/1.1 Pipelining or HTTP/2 multiplexing only
get additional transfers added to them if the existing connection is held by
the same multi or easy handle. libcurl does not support doing HTTP/2 streams
in different threads using a shared connection.

Support for \fBCURL_LOCK_DATA_CONNECT\fP was added in 7.57.0, but the symbol
existed before this.

Note that when you use the multi interface, all easy handles added to the same
multi handle will share connection cache by default without using this option.
.IP CURL_LOCK_DATA_PSL
The Public Suffix List stored in the share object is made available to all
easy handle bound to the later. Since the Public Suffix List is periodically
refreshed, this avoids updates in too many different contexts.

Added in 7.61.0.

Note that when you use the multi interface, all easy handles added to the same
multi handle will share PSL cache by default without using this option.
.SH PROTOCOLS
All
.SH EXAMPLE
.nf
  CURLSHcode sh;
  share = curl_share_init();
  sh = curl_share_setopt(share, CURLSHOPT_SHARE, CURL_LOCK_DATA_COOKIE);
  if(sh)
    printf("Error: %s\\n", curl_share_strerror(sh));
.fi
.SH AVAILABILITY
Added in 7.10
.SH RETURN VALUE
CURLSHE_OK (zero) means that the option was set properly, non-zero means an
error occurred. See \fIlibcurl-errors(3)\fP for the full list with
descriptions.
.SH "SEE ALSO"
.BR CURLSHOPT_UNSHARE "(3), "
.BR curl_share_setopt "(3), " curl_share_cleanup "(3), " curl_share_init "(3)"