---
c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
SPDX-License-Identifier: curl
Title: curl_global_cleanup
Section: 3
Source: libcurl
See-also:
  - curl_global_init (3)
  - libcurl (3)
  - libcurl-thread (3)
Protocol:
  - All
Added-in: 7.8
---

# NAME

curl_global_cleanup - global libcurl cleanup

# SYNOPSIS

~~~c
#include <curl/curl.h>

void curl_global_cleanup(void);
~~~

# DESCRIPTION

This function releases resources acquired by curl_global_init(3).

You should call curl_global_cleanup(3) once for each call you make to
curl_global_init(3), after you are done using libcurl.

This function is thread-safe since libcurl 7.84.0 if
curl_version_info(3) has the CURL_VERSION_THREADSAFE feature bit set
(most platforms).

If this is not thread-safe, you must not call this function when any other
thread in the program (i.e. a thread sharing the same memory) is running.
This does not just mean no other thread that is using libcurl. Because
curl_global_cleanup(3) calls functions of other libraries that are
similarly thread unsafe, it could conflict with any other thread that uses
these other libraries.

See the description in libcurl(3) of global environment requirements for
details of how to use this function.

# CAUTION

curl_global_cleanup(3) does not block waiting for any libcurl-created
threads to terminate (such as threads used for name resolving). If a module
containing libcurl is dynamically unloaded while libcurl-created threads are
still running then your program may crash or other corruption may occur. We
recommend you do not run libcurl from any module that may be unloaded
dynamically. This behavior may be addressed in the future.

libcurl may not be able to fully clean up after multi-threaded OpenSSL
depending on how OpenSSL was built and loaded as a library. It is possible in
some rare circumstances a memory leak could occur unless you implement your own
OpenSSL thread cleanup. Refer to libcurl-thread(3).

# %PROTOCOLS%

# EXAMPLE

~~~c
int main(void)
{
  curl_global_init(CURL_GLOBAL_DEFAULT);

  /* use libcurl, then before exiting... */

  curl_global_cleanup();
}
~~~

# %AVAILABILITY%

# RETURN VALUE

None
