in pdf2png: write to temp file instead of local file

Author: Accio

R/utils.R

@@ -177,8 +177,9 @@ ipdf <- function(file, ...) {
 #'   plot(1:5)
 #'   dev.off()
 #' 
+#'   pngfile <- file.path(tmpdir, "test.png")
 #'   pdf2png(pdffile)
-#'   pdf2png(pdffile, outfile="test.png")
+#'   pdf2png(pdffile, outfile=pngfile)
 #' 
 #'   testfile <- system.file("/doc/intro.pdf", package="limma")
 #'   if(file.exists(testfile)) {