CURLMOPT_PUSHDATA(3) Library Functions Manual CURLMOPT_PUSHDATA(3)

CURLMOPT_PUSHDATA - pointer to pass to push callback

#include <curl/curl.h>
CURLMcode curl_multi_setopt(CURLM *handle, CURLMOPT_PUSHDATA, void *pointer);

Set a pointer to pass as the last argument to the CURLMOPT_PUSHFUNCTION(3) callback. The pointer is not touched or used by libcurl itself, only passed on to the callback function.

NULL

This functionality affects http only

#include <string.h>
/* only allow pushes for filenames starting with "push-" */
int push_callback(CURL *parent,
                  CURL *easy,
                  size_t num_headers,
                  struct curl_pushheaders *headers,
                  void *clientp)
{
  char *headp;
  int *transfers = (int *)clientp;
  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;
}
int main(void)
{
  int counter;
  CURLM *multi = curl_multi_init();
  curl_multi_setopt(multi, CURLMOPT_PUSHFUNCTION, push_callback);
  curl_multi_setopt(multi, CURLMOPT_PUSHDATA, &counter);
}

Added in curl 7.44.0

Returns CURLM_OK if the option is supported, and CURLM_UNKNOWN_OPTION if not.

CURLMOPT_PIPELINING(3), CURLMOPT_PUSHFUNCTION(3), CURLOPT_PIPEWAIT(3), RFC7540

2024-09-18 libcurl