about curl functions curl_global_init / curl_easy_reset

[jparada]

Hi,

I have doubt when we use curl, for example, two independent functions one from the other, in each of the functions I must use curl_global_init, and another doubt, in some examples I have seen that at the end of the function they use curl_easy_reset( curl ), but in many other examples I see that this call is not used, what is the difference between using it or not, what is recommended, it depends on some other "special" call, what is the difference?.

I appreciate your help.

Regards,
Javier

[danielmaximiliano]

Hola Javier :
te recomiendo leer la API Curl
https://curl.se/libcurl/c/curl_easy_reset.html
https://curl.se/libcurl/c/curl_global_init.html

[vagblad]

Hi Javier,

curl_global_init() must be called at least once in your program, to setup the environment for the curl library to be used.

curl_easy_init() returns a handle number which you use whenever you call another curl function in order to identify for which specific curl handle you want. You can have multiple curl_easy_init() in your program for different procedures. For example:

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nCurlHandle_1 := curl_easy_init()
curl_easy_setopt( nCurlHandle_1, HB_CURLOPT_HTTPPOST, .T. ) //Setup this handle only for POST method so you dont have to change the curl_options for it everytime.
nCurlHandle_2 := curl_easy_init()
curl_easy_setopt( nCurlHandle_2, HB_CURLOPT_HTTPGET, .T. ) //Setup this handle only for GET method so you dont have to change the curl_options for it everytime.

or you can call multiple curl_easy_ini() and run each handle in a different thread. just be careful to call the curl_global_init() in the main thread because its not a thread safe function.

curl_easy_reset(CURL Handle) resets all the options(curl_easy_opt) for the specific handle to their default values.

For example in the above code:

Code: Select all

curl_easy_reset(nCurlHandle_1) //this will reset all the setup options for the nCurlHandle_1. so the curl_easy_setopt( nCurlHandle_1, HB_CURLOPT_HTTPPOST, .T. ) is no longer valid.

you can call curl_easy_reset() to reset the options for a specific handle and then re-setup another set of options for it while maintaining the current connection status, cache etc.