.\" **************************************************************************
.\" *                                  _   _ ____  _
.\" *  Project                     ___| | | |  _ \| |
.\" *                             / __| | | | |_) | |
.\" *                            | (__| |_| |  _ <| |___
.\" *                             \___|\___/|_| \_\_____|
.\" *
.\" * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
.\" *
.\" * This software is licensed as described in the file COPYING, which
.\" * you should have received as part of this distribution. The terms
.\" * are also available at https://curl.se/docs/copyright.html.
.\" *
.\" * You may opt to use, copy, modify, merge, publish, distribute and/or sell
.\" * copies of the Software, and permit persons to whom the Software is
.\" * furnished to do so, under the terms of the COPYING file.
.\" *
.\" * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
.\" * KIND, either express or implied.
.\" *
.\" * SPDX-License-Identifier: curl
.\" *
.\" **************************************************************************
.\"
.TH CURLMOPT_PUSHDATA 3 "September 26, 2023" "ibcurl 8.4.0" libcurl

.SH NAME
CURLMOPT_PUSHDATA \- pointer to pass to push callback
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURLMcode curl_multi_setopt(CURLM *handle, CURLMOPT_PUSHDATA, void *pointer);
.fi
.SH DESCRIPTION
Set a \fIpointer\fP to pass as the last argument to the
\fICURLMOPT_PUSHFUNCTION(3)\fP callback. The pointer is not touched or used by
libcurl itself, only passed on to the callback function.
.SH DEFAULT
NULL
.SH PROTOCOLS
HTTP(S)
.SH EXAMPLE
.nf
/* 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 *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;
}

curl_multi_setopt(multi, CURLMOPT_PUSHFUNCTION, push_callback);
curl_multi_setopt(multi, CURLMOPT_PUSHDATA, &counter);
.fi
.SH AVAILABILITY
Added in 7.44.0
.SH RETURN VALUE
Returns CURLM_OK if the option is supported, and CURLM_UNKNOWN_OPTION if not.
.SH "SEE ALSO"
.BR CURLMOPT_PIPELINING (3),
.BR CURLMOPT_PUSHFUNCTION (3),
.BR CURLOPT_PIPEWAIT (3),
.BR RFC 7540