curl/docs/libcurl/opts/CURLINFO_CONN_ID.3
Stefan Eissing e024d5665d
lib: add CURLINFO_CONN_ID and CURLINFO_XFER_ID
- add an `id` long to Curl_easy, -1 on init
- once added to a multi (or its own multi), it gets
  a non-negative number assigned by the connection cache
- `id` is unique among all transfers using the same
  cache until reaching LONG_MAX where it will wrap
  around. So, not unique eternally.
- CURLINFO_CONN_ID returns the connection id attached to
  data or, if none present, data->state.lastconnect_id
- variables and type declared in tool for write out

Closes #11185
2023-06-12 23:53:00 +02:00

70 lines
2.3 KiB
Groff

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.TH CURLINFO_CONN_ID 3 "07 June 2023" "libcurl" "libcurl"
.SH NAME
CURLINFO_CONN_ID \- get the ID of the last connection used by the handle
.SH SYNOPSIS
.nf
#include <curl/curl.h>
CURLcode curl_easy_getinfo(CURL *handle, CURLINFO_CONN_ID,
curl_off_t *conn_id);
.fi
.SH DESCRIPTION
Pass a pointer to a \fIcurl_off_t\fP to receive the connection identifier last
used by the handle. Stores -1 if there was no connection used.
The connection id is unique among all connections using the same
connection cache. This is implicitly the case for all connections in the
same multi handle.
.SH PROTOCOLS
All
.SH EXAMPLE
.nf
CURL *curl = curl_easy_init();
if(curl) {
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
/* Perform the request */
res = curl_easy_perform(curl);
if(!res) {
curl_off_t conn_id;
res = curl_easy_getinfo(curl, CURLINFO_CONN_ID, &conn_id);
if(!res) {
printf("Connection used: %" CURL_FORMAT_CURL_OFF_T "\\n", conn_id);
}
}
}
.fi
.SH AVAILABILITY
Added in 8.2.0
.SH RETURN VALUE
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.
.SH "SEE ALSO"
.BR curl_easy_getinfo "(3), " curl_easy_setopt "(3), "
.BR CURLINFO_XFER_ID "(3), "