Have read.dcf() recognize comment lines (PR#18903, by Dirk Eddelbuettel and Laurent Gatto).

git-svn-id: https://svn.r-project.org/R/trunk@88273 00db46b3-68df-0310-9c12-caf00c1e9a41

Author: hornik

src/library/base/R/dcf.R

@@ -75,6 +75,9 @@ function(file, fields = NULL, all = FALSE, keep.white = NULL)
 
     lines <- readLines(file, skipNul = TRUE, encoding = "bytes")
 
+    ## Ignore comment lines.
+    lines <- lines[!startsWith(lines, "#")]
+
     ## Try to find out about invalid things: mostly, lines which do not
     ## start with blanks but have no ':' ...
     ind <- grep(paste0("^[^", ascii_blank, "][^:]*$"), lines)

src/library/base/man/dcf.Rd

@@ -106,8 +106,7 @@ write.dcf(x, file = "", append = FALSE, useBytes = FALSE,
   \url{https://www.debian.org/doc/debian-policy/ch-controlfields.html}.
 
   Note that \R does not require encoding in UTF-8, which is a recent
-  Debian requirement.  Nor does it use the Debian-specific sub-format
-  which allows comment lines starting with \samp{#}.
+  Debian requirement.
 }
 
 \note{

src/main/dcf.c

@@ -149,6 +149,8 @@ attribute_hidden SEXP do_readDCF(SEXP call, SEXP op, SEXP args, SEXP env)
 		field_fold = true;
 		n_eblanklines = 0;
 	    }
+	} else if(line[0] == '#') {
+	    /* Ignore comment lines */
 	} else {
 	    blank_skip = false;
 	    if(tre_regexecb(&contline, line, 1, regmatch, 0) == 0) {