.\" generated by cd2nroff 0.1 from CURLOPT_UPLOAD.md
.TH CURLOPT_UPLOAD 3 "2024-08-02" libcurl
.SH NAME
CURLOPT_UPLOAD \- data upload
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_UPLOAD, long upload);
.fi
.SH DESCRIPTION
The long parameter \fIupload\fP set to 1 tells the library to prepare for and
perform an upload. The \fICURLOPT_READDATA(3)\fP and \fICURLOPT_INFILESIZE(3)\fP or
\fICURLOPT_INFILESIZE_LARGE(3)\fP 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 \fICURLOPT_HTTPHEADER(3)\fP 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
\fICURLOPT_INFILESIZE(3)\fP or \fICURLOPT_INFILESIZE_LARGE(3)\fP.
.SH DEFAULT
0
.SH PROTOCOLS
This functionality affects all supported protocols
.SH EXAMPLE
.nf
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);
  }
}
.fi
.SH AVAILABILITY
Added in curl 7.1
.SH RETURN VALUE
Returns CURLE_OK
.SH SEE ALSO
.BR CURLOPT_INFILESIZE_LARGE (3),
.BR CURLOPT_PUT (3),
.BR CURLOPT_READFUNCTION (3)