curl/docs/libcurl/curl_easy_duphandle.md
Daniel Stenberg e3fe020089
docs/libcurl: generate PROTOCOLS from meta-data
Remove the PROTOCOLS section from the source files completely and
instead generate them based on the header data in the curldown files.

It also generates TLS backend information for options marked for TLS as
protocol.

Closes #13175
2024-03-23 18:13:03 +01:00

75 lines
1.8 KiB
Markdown

---
c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
SPDX-License-Identifier: curl
Title: curl_easy_duphandle
Section: 3
Source: libcurl
See-also:
- curl_easy_cleanup (3)
- curl_easy_init (3)
- curl_easy_reset (3)
- curl_global_init (3)
Protocol:
- All
---
# NAME
curl_easy_duphandle - Clone a libcurl session handle
# SYNOPSIS
~~~c
#include <curl/curl.h>
CURL *curl_easy_duphandle(CURL *handle);
~~~
# DESCRIPTION
This function returns a new curl handle, a duplicate, using all the options
previously set in the input curl *handle*. Both handles can subsequently be
used independently and they must both be freed with curl_easy_cleanup(3).
Any options that the input handle has been told to point to (as opposed to
copy) with previous calls to curl_easy_setopt(3), are pointed to by the new
handle as well. You must therefore make sure to keep the data around until
both handles have been cleaned up.
The new handle does **not** inherit any state information, no connections, no
SSL sessions and no cookies. It also does not inherit any share object states
or options (created as if CURLOPT_SHARE(3) was set to NULL).
If the source handle has HSTS or alt-svc enabled, the duplicate gets data read
data from the main filename to populate the cache.
In multi-threaded programs, this function must be called in a synchronous way,
the input handle may not be in use when cloned.
# EXAMPLE
~~~c
int main(void)
{
CURL *curl = curl_easy_init();
if(curl) {
CURLcode res;
CURL *nother;
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
nother = curl_easy_duphandle(curl);
res = curl_easy_perform(nother);
curl_easy_cleanup(nother);
curl_easy_cleanup(curl);
}
}
~~~
# AVAILABILITY
Added in 7.9
# RETURN VALUE
If this function returns NULL, something went wrong and no valid handle was
returned.