curl/docs/libcurl/opts/CURLOPT_UPLOAD.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

2.3 KiB

c SPDX-License-Identifier Title Section Source See-also
Copyright (C) Daniel Stenberg, <daniel.se>, et al. curl CURLOPT_UPLOAD 3 libcurl
CURLOPT_INFILESIZE_LARGE (3)
CURLOPT_PUT (3)
CURLOPT_READFUNCTION (3)

NAME

CURLOPT_UPLOAD - data upload

SYNOPSIS

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_UPLOAD, long upload);

DESCRIPTION

The long parameter upload set to 1 tells the library to prepare for and perform an upload. The CURLOPT_READDATA(3) and CURLOPT_INFILESIZE(3) or CURLOPT_INFILESIZE_LARGE(3) options are also interesting for uploads. If the protocol is HTTP, uploading means using the PUT request unless you tell libcurl otherwise.

Using PUT with HTTP 1.1 implies the use of a "Expect: 100-continue" header. You can disable this header with CURLOPT_HTTPHEADER(3) as usual.

If you use PUT to an HTTP 1.1 server, you can upload data without knowing the size before starting the transfer. The library enables this by adding a header "Transfer-Encoding: chunked". With HTTP 1.0 or if you prefer not to use chunked transfer, you must specify the size of the data with CURLOPT_INFILESIZE(3) or CURLOPT_INFILESIZE_LARGE(3).

DEFAULT

0, default is download

PROTOCOLS

Most

EXAMPLE

static size_t read_cb(char *ptr, size_t size, size_t nmemb, void *userdata)
{
  FILE *src = userdata;
  /* copy as much data as possible into the 'ptr' buffer, but no more than
     'size' * 'nmemb' bytes */
  size_t retcode = fread(ptr, size, nmemb, src);

  return retcode;
}

int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    FILE *src = fopen("local-file", "r");
    curl_off_t fsize; /* set this to the size of the input file */

    /* we want to use our own read function */
    curl_easy_setopt(curl, CURLOPT_READFUNCTION, read_cb);

    /* enable uploading */
    curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L);

    /* specify target */
    curl_easy_setopt(curl, CURLOPT_URL, "ftp://example.com/dir/to/newfile");

    /* now specify which pointer to pass to our callback */
    curl_easy_setopt(curl, CURLOPT_READDATA, src);

    /* Set the size of the file to upload */
    curl_easy_setopt(curl, CURLOPT_INFILESIZE_LARGE, (curl_off_t)fsize);

    /* Now run off and do what you have been told! */
    curl_easy_perform(curl);
  }
}

AVAILABILITY

Always

RETURN VALUE

Returns CURLE_OK