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CURLMOPT_PUSHDATA - pointer to pass to push callback

#include <curl/curl.h>

CURLMcode curl_multi_setopt(CURLM *handle, CURLMOPT_PUSHDATA, void *pointer);

Set pointer to pass as the last argument to the CURLMOPT_PUSHFUNCTION(3) callback. The pointer will not be touched or used by libcurl itself, only passed on to the callback function. NULL HTTP(S)

/* only allow pushes for file names starting with "push-" */
int push_callback(CURL *parent,
 CURL *easy,
 size_t num_headers,
 struct curl_pushheaders *headers,
 void *userp)
{
 char *headp;
 int *transfers = (int *)userp;
 FILE *out;
 headp = curl_pushheader_byname(headers, ":path");
 if(headp && !strncmp(headp, "/push-", 6)) {
 fprintf(stderr, "The PATH is %s\\n", headp);

 /* save the push here */
 out = fopen("pushed-stream", "wb");

 /* write to this file */
 curl_easy_setopt(easy, CURLOPT_WRITEDATA, out);

 (*transfers)++; /* one more */

 return CURL_PUSH_OK;
 }
 return CURL_PUSH_DENY;
}

curl_multi_setopt(multi, CURLMOPT_PUSHFUNCTION, push_callback);
curl_multi_setopt(multi, CURLMOPT_PUSHDATA, &counter);

Added in 7.44.0 Returns CURLM_OK if the option is supported, and CURLM_UNKNOWN_OPTION if not. CURLMOPT_PUSHFUNCTION "(3), " CURLMOPT_PIPELINING "(3), " CURLOPT_PIPEWAIT "(3), " RFC 7540