Import C function from RCurl to avoid R CMD check problem

NAMESPACE

@@ -103,4 +103,5 @@ exportClasses(Token)
 exportClasses(Token1.0)
 exportClasses(Token2.0)
 import(stringr)
+useDynLib(httr,close_file)
 useDynLib(httr,writer)

R/write-function.R

@@ -67,8 +67,9 @@ write_opts.write_disk <- function(x) {
   )
 }
 #' @export
+#' @useDynLib httr close_file
 write_term.write_disk <- function(x) {
-  .Call("R_closeCFILE", x$file@ref, PACKAGE = "RCurl")
+  .Call(close_file, x$file@ref)
   x$file <- NULL
   path(x$path)
 }

src/writer.c

@@ -1,4 +1,6 @@
 #include <stdio.h>
+#include <R.h>
+#include <Rdefines.h>
 
 // From http://stackoverflow.com/questions/17329288/
 // License: http://creativecommons.org/licenses/by-sa/3.0/
@@ -7,3 +9,17 @@ size_t writer(void *buffer, size_t size, size_t nmemb, void *stream) {
   fwrite(buffer, size, nmemb, (FILE *) stream);
   return size * nmemb;
 }
+
+// From: RCurl
+// BSD_3_clause
+// YEAR: 2001-2014
+// COPYRIGHT HOLDER: Duncan Temple Lang
+// ORGANIZATION: Bell Labs, Lucent Technologies; University of California
+void close_file(SEXP r_file) {
+  FILE *f = (FILE *) R_ExternalPtrAddr(r_file);
+  if (f) {
+    fflush(f);
+    fclose(f);
+    R_SetExternalPtrAddr(r_file, NULL);
+  }
+}