postit2-formadd.c
/*************************************************************************** * _ _ ____ _ * Project ___| | | | _ \| | * / __| | | | |_) | | * | (__| |_| | _ <| |___ * \___|\___/|_| \_\_____| * * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. * * This software is licensed as described in the file COPYING, which * you should have received as part of this distribution. The terms * are also available at https://curl.se/docs/copyright.html. * * You may opt to use, copy, modify, merge, publish, distribute and/or sell * copies of the Software, and permit persons to whom the Software is * furnished to do so, under the terms of the COPYING file. * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY * KIND, either express or implied. * * SPDX-License-Identifier: curl * ***************************************************************************/ /* <DESC> * HTTP Multipart formpost with file upload and two additional parts. * </DESC> */ /* * Example code that uploads a filename 'foo' to a remote script that accepts * "HTML form based" (as described in RFC 1738) uploads using HTTP POST. * * Warning: this example uses the deprecated form api. See "postit2.c" * for a similar example using the mime api. * * The imaginary form we fill in looks like: * * <form method="post" enctype="multipart/form-data" action="examplepost.cgi"> * Enter file: <input type="file" name="sendfile" size="40"> * Enter filename: <input type="text" name="filename" size="30"> * <input type="submit" value="send" name="submit"> * </form> */ #include <stdio.h> #include <string.h> #include <curl/curl.h> int main(int argc, char *argv[]) { CURL *curl; CURLcode res; struct curl_httppost *formpost = NULL; struct curl_httppost *lastptr = NULL; struct curl_slist *headerlist = NULL; static const char buf[] = "Expect:"; curl_global_init(CURL_GLOBAL_ALL); CURL_IGNORE_DEPRECATION( /* Fill in the file upload field */ curl_formadd(&formpost, &lastptr, CURLFORM_COPYNAME, "sendfile", CURLFORM_FILE, "postit2-formadd.c", CURLFORM_END); /* Fill in the filename field */ curl_formadd(&formpost, &lastptr, CURLFORM_COPYNAME, "filename", CURLFORM_COPYCONTENTS, "postit2-formadd.c", CURLFORM_END); /* Fill in the submit field too, even if this is rarely needed */ curl_formadd(&formpost, &lastptr, CURLFORM_COPYNAME, "submit", CURLFORM_COPYCONTENTS, "send", CURLFORM_END); ) curl = curl_easy_init(); /* initialize custom header list (stating that Expect: 100-continue is not wanted */ headerlist = curl_slist_append(headerlist, buf); if(curl) { /* what URL that receives this POST */ curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/examplepost.cgi"); if((argc == 2) && (!strcmp(argv[1], "noexpectheader"))) /* only disable 100-continue header if explicitly requested */ curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headerlist); CURL_IGNORE_DEPRECATION( curl_easy_setopt(curl, CURLOPT_HTTPPOST, formpost); ) /* Perform the request, res gets the return code */ res = curl_easy_perform(curl); /* Check for errors */ if(res != CURLE_OK) fprintf(stderr, "curl_easy_perform() failed: %s\n", curl_easy_strerror(res)); /* always cleanup */ curl_easy_cleanup(curl); CURL_IGNORE_DEPRECATION( /* then cleanup the formpost chain */ curl_formfree(formpost); ) /* free slist */ curl_slist_free_all(headerlist); } return 0; }
Notice
This source code example is simplified and ignores return
codes and error checks to a large extent. We do this to highlight the libcurl
function calls and related options and reduce unrelated code.
A real-world application will of course properly check every return value and exit correctly at the first serious error.