Provided by: libcurl4-doc_7.65.3-1ubuntu3_all 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

       This function is deprecated. Do not use! See curl_mime_init(3) instead!

       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(3).  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 firstitem 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(3) 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, you must set its length with CURLFORM_NAMELENGTH.
              The name is not allowed to contain zero-valued bytes. 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, you must  set  its
              length  with  CURLFORM_NAMELENGTH.   The name is not allowed to contain zero-valued
              bytes.

       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_CONTENTLEN
              followed by a curl_off_t value giving the length of the  contents.  Note  that  for
              CURLFORM_STREAM contents, this option is mandatory.

              If  you  pass a 0 (zero) for this option, libcurl will instead do a strlen() on the
              contents to figure out the size. If you really want to send  a  zero  byte  content
              then you must make sure strlen() on the data pointer returns zero.

              (Option added in 7.46.0)

       CURLFORM_CONTENTSLENGTH
              (This option is deprecated. Use CURLFORM_CONTENTLEN instead!)

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

              If you pass a 0 (zero) for this option, libcurl will instead do a strlen()  on  the
              contents  to  figure  out  the size. If you really want to send a zero byte content
              then you must make sure strlen() on the data pointer returns zero.

       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.

              The specified file needs to kept around until the associated transfer is done.

       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).

              The  given upload file has to exist in its full in the file system already when the
              upload starts, as libcurl needs to read the correct file size beforehand.

              The specified file needs to kept around until the associated transfer is done.

       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(3)  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
              unless the formpost is sent chunked encoded. (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(3) option), you must not free the list until after  you've  called
              curl_easy_cleanup(3) for the curl handle.

              See example below.

AVAILABILITY

       Deprecated in 7.56.0. Before this release, field names were allowed to contain zero-valued
       bytes. The pseudo-filename "-" to read stdin is discouraged although still supported,  but
       data  is  not  read  before  being  actually sent: the effective data size can then not be
       automatically determined, resulting in a chunked encoding transfer. Backslashes and double
       quotes in field and file names are now escaped before transmission.

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), curl_mime_init(3)