Provided by: libcurl4-openssl-dev_7.22.0-3ubuntu4_amd64 bug

NAME

       curl_formadd - add a section to a multipart/formdata HTTP POST

SYNOPSIS

       #include <curl/curl.h>

       CURLFORMcode  curl_formadd(struct  curl_httppost  **  firstitem,  struct  curl_httppost **
       lastitem, ...);

DESCRIPTION

       curl_formadd() is used to append sections when building  a  multipart/formdata  HTTP  POST
       (sometimes  referred to as RFC2388-style posts). Append one section at a time until you've
       added all the sections you want included and  then  you  pass  the  firstitem  pointer  as
       parameter  to  CURLOPT_HTTPPOST.   lastitem  is set after each curl_formadd(3) call and on
       repeated invokes it should be left as set to allow repeated invokes to find the end of the
       list faster.

       After the lastitem pointer follow the real arguments.

       The  pointers  firstitem and lastitem should both be pointing to NULL in the first call to
       this function. All list-data will be allocated by  the  function  itself.  You  must  call
       curl_formfree(3)  on  the  firstitemP  after  the  form  post  has  been  done to free the
       resources.

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

       First,  there  are some basics you need to understand about multipart/formdata posts. Each
       part consists of at least a NAME and a CONTENTS part. If the part is made for file upload,
       there  are  also  a stored CONTENT-TYPE and a FILENAME.  Below, we'll discuss what options
       you use to set these properties in the parts you want to add to your post.

       The options listed first are for making  normal  parts.  The  options  from  CURLFORM_FILE
       through CURLFORM_BUFFERLENGTH are for file upload parts.

OPTIONS

       CURLFORM_COPYNAME
              followed  by  a  string  which  provides  the name of this part. libcurl copies the
              string so your application doesn't need to keep it around after this function call.
              If  the  name  isn't NUL-terminated, or if you'd like it to contain zero bytes, you
              must set its length with CURLFORM_NAMELENGTH. The copied  data  will  be  freed  by
              curl_formfree(3).

       CURLFORM_PTRNAME
              followed  by  a  string  which provides the name of this part. libcurl will use the
              pointer and refer to the data in your application, so you must make sure it remains
              until  curl  no longer needs it. If the name isn't NUL-terminated, or if you'd like
              it to contain zero bytes, you must set its length with CURLFORM_NAMELENGTH.

       CURLFORM_COPYCONTENTS
              followed by a pointer to the contents of this part, the actual data to  send  away.
              libcurl  copies  the  provided  data,  so  your application doesn't need to keep it
              around after this function call. If the data isn't null  terminated,  or  if  you'd
              like  it  to  contain  zero  bytes,  you  must  set  the  length  of  the name with
              CURLFORM_CONTENTSLENGTH. The copied data will be freed by curl_formfree(3).

       CURLFORM_PTRCONTENTS
              followed by a pointer to the contents of this part, the actual data to  send  away.
              libcurl will use the pointer and refer to the data in your application, so you must
              make sure it remains until curl no  longer  needs  it.   If  the  data  isn't  NUL-
              terminated,  or  if  you'd  like  it to contain zero bytes, you must set its length
              with CURLFORM_CONTENTSLENGTH.

       CURLFORM_CONTENTSLENGTH
              followed by a long giving the length of the contents. Note that for CURLFORM_STREAM
              contents, this option is mandatory.

       CURLFORM_FILECONTENT
              followed  by  a filename, causes that file to be read and its contents used as data
              in this part. This part does not automatically become a  file  upload  part  simply
              because its data was read from a file.

       CURLFORM_FILE
              followed  by  a  filename, makes this part a file upload part. It sets the filename
              field to the basename of the provided filename, it reads the contents of  the  file
              and  passes  them  as data and sets the content-type if the given file match one of
              the internally known file extensions.  For CURLFORM_FILE the user may send  one  or
              more  files in one part by providing multiple CURLFORM_FILE arguments each followed
              by the filename (and each CURLFORM_FILE is allowed to have a CURLFORM_CONTENTTYPE).

       CURLFORM_CONTENTTYPE
              is used in combination with CURLFORM_FILE. Followed by a pointer to a string  which
              provides  the  content-type for this part, possibly instead of an internally chosen
              one.

       CURLFORM_FILENAME
              is used in combination with CURLFORM_FILE. Followed by a pointer to  a  string,  it
              tells  libcurl  to  use  the  given  string as the filename in the file upload part
              instead of the actual file name.

       CURLFORM_BUFFER
              is used for custom file upload  parts  without  use  of  CURLFORM_FILE.   It  tells
              libcurl that the file contents are already present in a buffer.  The parameter is a
              string which provides the filename field in the content header.

       CURLFORM_BUFFERPTR
              is used in combination with CURLFORM_BUFFER. The parameter  is  a  pointer  to  the
              buffer   to   be   uploaded.   This   buffer   must   not   be  freed  until  after
              curl_easy_cleanup(3) is called. You must also use CURLFORM_BUFFERLENGTH to set  the
              number of bytes in the buffer.

       CURLFORM_BUFFERLENGTH
              is  used  in  combination with CURLFORM_BUFFER. The parameter is a long which gives
              the length of the buffer.

       CURLFORM_STREAM
              Tells libcurl to use the CURLOPT_READFUNCTION callback to get data.  The  parameter
              you  pass to CURLFORM_STREAM is the pointer passed on to the read callback's fourth
              argument. If  you  want  the  part  to  look  like  a  file  upload  one,  set  the
              CURLFORM_FILENAME   parameter  as  well.  Note  that  when  using  CURLFORM_STREAM,
              CURLFORM_CONTENTSLENGTH must also be set with the  total  expected  length  of  the
              part. (Option added in libcurl 7.18.2)

       CURLFORM_ARRAY
              Another possibility to send options to curl_formadd() is the CURLFORM_ARRAY option,
              that passes a struct  curl_forms  array  pointer  as  its  value.  Each  curl_forms
              structure element has a CURLformoption and a char pointer. The final element in the
              array must be a CURLFORM_END. All available options can be used in an array, except
              the  CURLFORM_ARRAY  option itself!  The last argument in such an array must always
              be CURLFORM_END.

       CURLFORM_CONTENTHEADER
              specifies extra headers for  the  form  POST  section.   This  takes  a  curl_slist
              prepared  in  the usual way using curl_slist_append and appends the list of headers
              to those libcurl automatically generates.  The  list  must  exist  while  the  POST
              occurs, if you free it before the post completes you may experience problems.

              When   you've  passed  the  HttpPost  pointer  to  curl_easy_setopt(3)  (using  the
              CURLOPT_HTTPPOST option), you must not free the  list  until  after  you've  called
              curl_easy_cleanup(3) for the curl handle.

              See example below.

RETURN VALUE

       0  means  everything  was  ok,  non-zero  means  an  error  occurred  corresponding  to  a
       CURL_FORMADD_* constant defined in <curl/curl.h>

EXAMPLE

        struct curl_httppost* post = NULL;
        struct curl_httppost* last = NULL;
        char namebuffer[] = "name buffer";
        long namelength = strlen(namebuffer);
        char buffer[] = "test buffer";
        char htmlbuffer[] = "<HTML>test buffer</HTML>";
        long htmlbufferlength = strlen(htmlbuffer);
        struct curl_forms forms[3];
        char file1[] = "my-face.jpg";
        char file2[] = "your-face.jpg";
        /* add null character into htmlbuffer, to demonstrate that
           transfers of buffers containing null characters actually work
        */
        htmlbuffer[8] = '\0';

        /* Add simple name/content section */
        curl_formadd(&post, &last, CURLFORM_COPYNAME, "name",
                     CURLFORM_COPYCONTENTS, "content", CURLFORM_END);

        /* Add simple name/content/contenttype section */
        curl_formadd(&post, &last, CURLFORM_COPYNAME, "htmlcode",
                     CURLFORM_COPYCONTENTS, "<HTML></HTML>",
                     CURLFORM_CONTENTTYPE, "text/html", CURLFORM_END);

        /* Add name/ptrcontent section */
        curl_formadd(&post, &last, CURLFORM_COPYNAME, "name_for_ptrcontent",
                     CURLFORM_PTRCONTENTS, buffer, CURLFORM_END);

        /* Add ptrname/ptrcontent section */
        curl_formadd(&post, &last, CURLFORM_PTRNAME, namebuffer,
                     CURLFORM_PTRCONTENTS, buffer, CURLFORM_NAMELENGTH,
                     namelength, CURLFORM_END);

        /* Add name/ptrcontent/contenttype section */
        curl_formadd(&post, &last, CURLFORM_COPYNAME, "html_code_with_hole",
                     CURLFORM_PTRCONTENTS, htmlbuffer,
                     CURLFORM_CONTENTSLENGTH, htmlbufferlength,
                     CURLFORM_CONTENTTYPE, "text/html", CURLFORM_END);

        /* Add simple file section */
        curl_formadd(&post, &last, CURLFORM_COPYNAME, "picture",
                     CURLFORM_FILE, "my-face.jpg", CURLFORM_END);

        /* Add file/contenttype section */
        curl_formadd(&post, &last, CURLFORM_COPYNAME, "picture",
                     CURLFORM_FILE, "my-face.jpg",
                     CURLFORM_CONTENTTYPE, "image/jpeg", CURLFORM_END);

        /* Add two file section */
        curl_formadd(&post, &last, CURLFORM_COPYNAME, "pictures",
                     CURLFORM_FILE, "my-face.jpg",
                     CURLFORM_FILE, "your-face.jpg", CURLFORM_END);

        /* Add two file section using CURLFORM_ARRAY */
        forms[0].option = CURLFORM_FILE;
        forms[0].value  = file1;
        forms[1].option = CURLFORM_FILE;
        forms[1].value  = file2;
        forms[2].option  = CURLFORM_END;

        /* Add a buffer to upload */
        curl_formadd(&post, &last,
                     CURLFORM_COPYNAME, "name",
                     CURLFORM_BUFFER, "data",
                     CURLFORM_BUFFERPTR, record,
                     CURLFORM_BUFFERLENGTH, record_length,
                     CURLFORM_END);

        /* no option needed for the end marker */
        curl_formadd(&post, &last, CURLFORM_COPYNAME, "pictures",
                     CURLFORM_ARRAY, forms, CURLFORM_END);
        /* Add the content of a file as a normal post text value */
        curl_formadd(&post, &last, CURLFORM_COPYNAME, "filecontent",
                     CURLFORM_FILECONTENT, ".bashrc", CURLFORM_END);
        /* Set the form info */
        curl_easy_setopt(curl, CURLOPT_HTTPPOST, post);

SEE ALSO

       curl_easy_setopt(3), curl_formfree(3)