NAME

       CURLOPT_POSTFIELDS - data to POST to server

SYNOPSIS

       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_POSTFIELDS, char *postdata);

DESCRIPTION

       Pass  a  char  * as parameter, pointing to the full data to send in an HTTP POST operation. You must make
       sure that the data is formatted the way you want the server to receive it. libcurl will  not  convert  or
       encode it for you in any way. For example, the web server may assume that this data is url-encoded.

       The  data  pointed to is NOT copied by the library: as a consequence, it must be preserved by the calling
       application until the associated transfer finishes.  This behavior can be changed (so libcurl  does  copy
       the data) by setting the CURLOPT_COPYPOSTFIELDS(3) option.

       This  POST  is a normal application/x-www-form-urlencoded kind (and libcurl will set that Content-Type by
       default when this option is used), which is  commonly  used  by  HTML  forms.  Change  Content-Type  with
       CURLOPT_HTTPHEADER(3).

       You can use curl_easy_escape(3) to url-encode your data, if necessary. It returns a pointer to an encoded
       string that can be passed as postdata.

       Using CURLOPT_POSTFIELDS(3) implies setting CURLOPT_POST(3) to 1.

       If  CURLOPT_POSTFIELDS(3)  is  explicitly  set  to NULL then libcurl will get the POST data from the read
       callback. If you want to send a zero-byte POST set CURLOPT_POSTFIELDS(3)  to  an  empty  string,  or  set
       CURLOPT_POST(3) to 1 and CURLOPT_POSTFIELDSIZE(3) to 0.

       libcurl   will   use  assume  this  option  points  to  a  nul-terminated  string  unless  you  also  set
       CURLOPT_POSTFIELDSIZE(3) to specify the length of the provided data, which then is strictly  required  if
       you want to send off nul bytes included in the data.

       Using  POST  with  HTTP 1.1 implies the use of a "Expect: 100-continue" header, and libcurl will add that
       header automatically if the POST is either known to be larger  than  1MB  or  if  the  expected  size  is
       unknown. You can disable this header with CURLOPT_HTTPHEADER(3) as usual.

       To  make  multipart/formdata posts (aka RFC2388-posts), check out the CURLOPT_HTTPPOST(3) option combined
       with curl_formadd(3).

DEFAULT

       NULL

PROTOCOLS

       HTTP

EXAMPLE

       CURL *curl = curl_easy_init();
       if(curl) {
         const char *data = "data to send";

         curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");

         /* size of the POST data */
         curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE, 12L);

         /* pass in a pointer to the data - libcurl will not copy */
         curl_easy_setopt(curl, CURLOPT_POSTFIELDS, data);

         curl_easy_perform(curl);
       }

AVAILABILITY

       Always

RETURN VALUE

       Returns CURLE_OK

SEE ALSO

       CURLOPT_POSTFIELDSIZE(3), CURLOPT_READFUNCTION(3),

libcurl 7.81.0                                  November 26, 2021                          CURLOPT_POSTFIELDS(3)