curl/docs/libcurl/curl_formget.3

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.TH curl_formget 3 "20 June 2006" "libcurl" "libcurl"
.SH NAME
curl_formget - serialize a previously built multipart form POST chain
.SH SYNOPSIS
.nf
.B #include <curl/curl.h>

int curl_formget(struct curl_httppost * form, void *userp,
                  curl_formget_callback append );
.SH DESCRIPTION
curl_formget() is used to serialize data previously built/appended with
\fIcurl_formadd(3)\fP. Accepts a void pointer as second argument named
\fIuserp\fP which will be passed as the first argument to the
curl_formget_callback function.

.BI "typedef size_t (*curl_formget_callback)(void *" userp, " const char *" buf,
.BI " size_t " len ");"

The curl_formget_callback will be executed for each part of the HTTP POST
chain. The character buffer passed to the callback must not be freed. The
callback should return the buffer length passed to it on success.

If the \fBCURLFORM_STREAM\fP option is used in the formpost, it will prevent
\fIcurl_formget(3)\fP from working until you have performed the actual HTTP
request as only then will libcurl get the actual read callback to use!
.SH EXAMPLE
.nf
 size_t print_httppost_callback(void *arg, const char *buf, size_t len)
 {
   fwrite(buf, len, 1, stdout);
   (*(size_t *) arg) += len;
   return len;
 }

 size_t print_httppost(struct curl_httppost *post)
 {
   size_t total_size = 0;
   if(curl_formget(post, &total_size, print_httppost_callback)) {
     return (size_t) -1;
   }
   return total_size;
 }
.SH AVAILABILITY
This function was added in libcurl 7.15.5. The form API is deprecated in
libcurl 7.56.0.
.SH RETURN VALUE
0 means everything was OK, non-zero means an error occurred
.SH "SEE ALSO"
.BR curl_formadd "(3), " curl_mime_init "(3)"