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curl_global_init(3)             libcurl Manual             curl_global_init(3)


       curl_global_init - Global libcurl initialization


       #include <curl/curl.h>

       CURLcode curl_global_init(long flags);


       This function sets up the program environment that libcurl needs. Think
       of it as an extension of the library loader.

       This function must be called at least once within a program (a program is
       all the code that shares a memory space) before the program calls any
       other function in libcurl. The environment it sets up is constant for the
       life of the program and is the same for every program, so multiple calls
       have the same effect as one call.

       The flags option is a bit pattern that tells libcurl exactly what
       features to init, as described below. Set the desired bits by ORing the
       values together.  In normal operation, you must specify CURL_GLOBAL_ALL.
       Do not use any other value unless you are familiar with it and mean to
       control internal operations of 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_init(3) calls functions of other libraries that are
       similarly thread unsafe, it could conflict with any other thread that
       uses these other libraries.

       If you are initializing libcurl from a Windows DLL you should not
       initialize it from DllMain or a static initializer because Windows holds
       the loader lock during that time and it could cause a deadlock.

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


              Initialize everything possible. This sets all known bits except

              (This flag's presence or absence serves no meaning since 7.57.0.
              The description below is for older libcurl versions.)

              Initialize SSL.

              The implication here is that if this bit is not set, the
              initialization of the SSL layer needs to be done by the
              application or at least outside of libcurl. The exact procedure
              how to do SSL initialization depends on the TLS backend libcurl

              Doing TLS based transfers without having the TLS layer initialized
              may lead to unexpected behaviors.

              Initialize the Win32 socket libraries.

              The implication here is that if this bit is not set, the
              initialization of winsock has to be done by the application or you
              risk getting undefined behaviors. This option exists for when the
              initialization is handled outside of libcurl so there's no need
              for libcurl to do it again.

              Initialize nothing extra. This sets no bit.

              A sensible default. It will init both SSL and Win32. Right now,
              this equals the functionality of the CURL_GLOBAL_ALL mask.

              This bit has no point since 7.69.0 but its behavior is instead the

              Before 7.69.0: when this flag is set, curl will acknowledge EINTR
              condition when connecting or when waiting for data. Otherwise,
              curl waits until full timeout elapses. (Added in 7.30.0)



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



       Added in 7.8


       If this function returns non-zero, something went wrong and you cannot
       use the other curl functions.


       curl_global_init_mem(3),  curl_global_cleanup(3),  curl_global_sslset(3),
       curl_easy_init(3)  libcurl(3)

libcurl 7.86.0                 September 20, 2022            curl_global_init(3)

curl 7.86.0 - Generated Tue Nov 1 08:11:48 CDT 2022
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