curl_global_cleanup - global libcurl cleanup

Added in curl 7.8

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).

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.

int main(void) { curl_global_init(CURL_GLOBAL_DEFAULT); /* use libcurl, then before exiting... */ curl_global_cleanup(); }

curl_global_cleanup - global libcurl cleanup

This functionality affects all supported protocols

None

curl_global_init(3), libcurl(3), libcurl-thread(3) libcurl 2025-06-16 curl_global_cleanup(3)

#include <curl/curl.h> void curl_global_cleanup(void);