curl/docs/libcurl/opts/CURLOPT_XFERINFODATA.md
Daniel Stenberg eefcc1bda4
docs: introduce "curldown" for libcurl man page format
curldown is this new file format for libcurl man pages. It is markdown
inspired with differences:

- Each file has a set of leading headers with meta-data
- Supports a small subset of markdown
- Uses .md file extensions for editors/IDE/GitHub to treat them nicely
- Generates man pages very similar to the previous ones
- Generates man pages that still convert nicely to HTML on the website
- Detects and highlights mentions of curl symbols automatically (when
  their man page section is specified)

tools:

- cd2nroff: converts from curldown to nroff man page
- nroff2cd: convert an (old) nroff man page to curldown
- cdall: convert many nroff pages to curldown versions
- cd2cd: verifies and updates a curldown to latest curldown

This setup generates .3 versions of all the curldown versions at build time.

CI:

Since the documentation is now technically markdown in the eyes of many
things, the CI runs many more tests and checks on this documentation,
including proselint, link checkers and tests that make sure we capitalize the
first letter after a period...

Closes #12730
2024-01-23 00:29:02 +01:00

1.4 KiB

c SPDX-License-Identifier Title Section Source See-also
Copyright (C) Daniel Stenberg, <daniel.se>, et al. curl CURLOPT_XFERINFODATA 3 libcurl
CURLOPT_NOPROGRESS (3)
CURLOPT_VERBOSE (3)
CURLOPT_XFERINFOFUNCTION (3)

NAME

CURLOPT_XFERINFODATA - pointer passed to the progress callback

SYNOPSIS

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_XFERINFODATA, void *pointer);

DESCRIPTION

Pass a pointer that is untouched by libcurl and passed as the first argument in the progress callback set with CURLOPT_XFERINFOFUNCTION(3).

This is an alias for CURLOPT_PROGRESSDATA(3).

DEFAULT

The default value of this parameter is NULL.

PROTOCOLS

All

EXAMPLE

struct progress {
  char *private;
  size_t size;
};

static size_t progress_cb(void *clientp,
                          curl_off_t dltotal,
                          curl_off_t dlnow,
                          curl_off_t ultotal,
                          curl_off_t ulnow)
{
  struct progress *memory = clientp;
  printf("private ptr: %p\n", memory->private);
  /* use the values */

  return 0; /* all is good */
}

int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    struct progress data;

    /* pass struct to callback  */
    curl_easy_setopt(curl, CURLOPT_XFERINFODATA, &data);
    curl_easy_setopt(curl, CURLOPT_XFERINFOFUNCTION, progress_cb);
  }
}

AVAILABILITY

Added in 7.32.0

RETURN VALUE

Returns CURLE_OK