Update networking layer w/ CURL and emscripten impl

External/curl-8.17.0/docs/libcurl/opts/CURLOPT_POSTFIELDSIZE.md

@@ -0,0 +1,75 @@
+---
+c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
+SPDX-License-Identifier: curl
+Title: CURLOPT_POSTFIELDSIZE
+Section: 3
+Source: libcurl
+See-also:
+  - CURLOPT_POSTFIELDS (3)
+  - CURLOPT_POSTFIELDSIZE_LARGE (3)
+Protocol:
+  - HTTP
+  - MQTT
+  - RTSP
+Added-in: 7.2
+---
+
+# NAME
+
+CURLOPT_POSTFIELDSIZE - size of POST data pointed to
+
+# SYNOPSIS
+
+~~~c
+#include <curl/curl.h>
+
+CURLcode curl_easy_setopt(CURL *handle, CURLOPT_POSTFIELDSIZE, long size);
+~~~
+
+# DESCRIPTION
+
+If you want to post static data to the server without having libcurl do a
+strlen() to measure the data size, this option must be used. When this option
+is used you can post fully binary data, which otherwise is likely to fail. If
+this size is set to -1, libcurl uses strlen() to get the size or relies on the
+CURLOPT_READFUNCTION(3) (if used) to signal the end of data.
+
+If you post more than 2GB, use CURLOPT_POSTFIELDSIZE_LARGE(3).
+
+# DEFAULT
+
+-1
+
+# %PROTOCOLS%
+
+# EXAMPLE
+
+~~~c
+#include <string.h> /* for strlen */
+
+int main(void)
+{
+  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, (long)strlen(data));
+
+    curl_easy_setopt(curl, CURLOPT_POSTFIELDS, data);
+
+    curl_easy_perform(curl);
+  }
+}
+~~~
+
+# %AVAILABILITY%
+
+# RETURN VALUE
+
+curl_easy_setopt(3) returns a CURLcode indicating success or error.
+
+CURLE_OK (0) means everything was OK, non-zero means an error occurred, see
+libcurl-errors(3).