diff --git a/main.c b/main.c
index 54801ed..e9e7013 100644
--- a/main.c
+++ b/main.c
@@ -40,7 +40,7 @@ main(int argc, char **argv)
 
     opterr = 1;
 
-    while ( (opt=getopt(argc, argv, "do:V")) != EOF ) {
+    while ( (opt=getopt(argc, argv, "dF:o:V")) != EOF ) {
 	switch (opt) {
 	case 'd':   debug = 1;
 		    break;
@@ -53,6 +53,8 @@ main(int argc, char **argv)
 #endif
 		    putchar('\n');
 		    exit(0);
+	case 'F':   flags = strtol(optarg, 0, 0);
+		    break;
 	case 'o':   if ( ofile ) {
 			fprintf(stderr, "Too many -o options\n");
 			exit(1);
@@ -74,9 +76,9 @@ main(int argc, char **argv)
 	exit(1);
     }
     if ( debug )
-	rc = mkd_dump(mkd_in(stdin), stdout, 0,
+	rc = mkd_dump(mkd_in(stdin, flags), stdout, 0,
 		      argc ? basename(argv[0]) : "stdin");
     else
-	rc = markdown(mkd_in(stdin), stdout, flags);
+	rc = markdown(mkd_in(stdin, flags), stdout, flags);
     exit( (rc == 0) ? 0 : errno );
 }
diff --git a/markdown.c b/markdown.c
index 1f5521a..2fc10fb 100644
--- a/markdown.c
+++ b/markdown.c
@@ -860,7 +860,7 @@ mkd_compile(Document *doc, FILE *out, int flags, MMIOT *ctx)
     doc->compiled = 1;
     bzero(ctx, sizeof *ctx);
     ctx->out = out;
-    ctx->flags = flags;
+    ctx->flags = flags & DENY_MASK;
     CREATE(ctx->in);
     CREATE(ctx->footnotes);
 
diff --git a/markdown.h b/markdown.h
index 3125098..f409a48 100644
--- a/markdown.h
+++ b/markdown.h
@@ -65,20 +65,25 @@ typedef struct mmiot {
     int isp;
     STRING(Footnote) footnotes;
     int flags;
-#define DENY_A		0x01
-#define DENY_IMG	0x02
-#define DENY_SMARTY	0x04
-#define EXPAND_QUOTE	0x10
+#define DENY_A		0x0001
+#define DENY_IMG	0x0002
+#define DENY_SMARTY	0x0004
+#define DENY_MASK	(DENY_A|DENY_IMG|DENY_SMARTY)
+#define EXPAND_QUOTE	0x0010
 } MMIOT;
 
+
 extern int    mkd_firstnonblank(Line *);
 extern int    mkd_compile(Document *, FILE *, int, MMIOT *);
 extern void   mkd_generatehtml(Document *, MMIOT *);
 extern void   mkd_cleanup(Document *, MMIOT *);
 extern int    mkd_text(char *, int, FILE*, int);
 
-extern Document *mkd_in(FILE *);
-extern Document *mkd_string(char*,int);
+extern Document *mkd_in(FILE *, int);
+extern Document *mkd_string(char*,int, int);
+
+#define NO_HEADER	0x0100
+#define INPUT_MASK	(NO_HEADER)
 
 
 #endif/*_MARKDOWN_D*/
diff --git a/mkdio.c b/mkdio.c
index 6336e16..109a245 100644
--- a/mkdio.c
+++ b/mkdio.c
@@ -66,7 +66,7 @@ queue(Document* a, Cstring *line)
 typedef unsigned int (*getc_func)(void*);
 
 Document *
-populate(getc_func getc, void* ctx)
+populate(getc_func getc, void* ctx, int flags)
 {
     Cstring line;
     Document *a = new_Document();
@@ -102,7 +102,7 @@ populate(getc_func getc, void* ctx)
     DELETE(line);
 
 #ifdef PANDOC_HEADER
-    if ( pandoc == 3 ) {
+    if ( (pandoc == 3) && !(flags & NO_HEADER) ) {
 	/* the first three lines started with %, so we have a header.
 	 * clip the first three lines out of content and hang them
 	 * off header.
@@ -120,9 +120,9 @@ populate(getc_func getc, void* ctx)
 /* convert a file into a linked list
  */
 Document *
-mkd_in(FILE *f)
+mkd_in(FILE *f, int flags)
 {
-    return populate((getc_func)fgetc, f);
+    return populate((getc_func)fgetc, f, flags & INPUT_MASK);
 }
 
 
@@ -148,12 +148,12 @@ strget(struct string_ctx *in)
 /* convert a block of text into a linked list
  */
 Document *
-mkd_string(char *buf, int len)
+mkd_string(char *buf, int len, int flags)
 {
     struct string_ctx about;
 
     about.data = buf;
     about.size = len;
 
-    return populate((getc_func)strget, &about);
+    return populate((getc_func)strget, &about, flags & INPUT_MASK);
 }
diff --git a/mkdio.h b/mkdio.h
index 4928947..751aa1d 100644
--- a/mkdio.h
+++ b/mkdio.h
@@ -5,8 +5,8 @@
 
 /* line builder for markdown()
  */
-void *mkd_in(FILE*);			/* assemble input from a file */
-void *mkd_string(char*,int);		/* assemble input from a buffer */
+void *mkd_in(FILE*,int);		/* assemble input from a file */
+void *mkd_string(char*,int,int);	/* assemble input from a buffer */
 
 /* compilation, debugging, cleanup
  */
@@ -21,8 +21,12 @@ int markdown(void*, FILE*, int);
 
 /* special flags for markdown() and mkd_text()
  */
-#define MKD_NOLINKS	0x01	/* don't do link processing, block <a> tags  */
-#define MKD_NOIMAGE	0x02	/* don't do image processing, block <img> */
-#define MKD_NOPANTS	0x04	/* don't run smartypants() */
+#define MKD_NOLINKS	0x0001	/* don't do link processing, block <a> tags  */
+#define MKD_NOIMAGE	0x0002	/* don't do image processing, block <img> */
+#define MKD_NOPANTS	0x0004	/* don't run smartypants() */
+
+/* special flags for mkd_in() and mkd_string()
+ */
+#define MKD_NOHEADER	0x0100	/* don't process header blocks */
 
 #endif/*_MKDIO_D*/
diff --git a/tests/code.t b/tests/code.t
index 50609f4..3dc447d 100644
--- a/tests/code.t
+++ b/tests/code.t
@@ -1,6 +1,7 @@
 echo "code blocks"
 
 rc=0
+MARKDOWN_FLAGS=
 
 echo -n '  format for code block html ....... '
 
diff --git a/tests/crash.t b/tests/crash.t
index b04d215..78905fe 100644
--- a/tests/crash.t
+++ b/tests/crash.t
@@ -1,6 +1,7 @@
 echo "crashes"
 
 rc=0
+MARKDOWN_FLAGS=
 
 echo -n '  zero-length input ................ '
 
diff --git a/tests/dl.t b/tests/dl.t
index 2a09c24..a62fb1e 100644
--- a/tests/dl.t
+++ b/tests/dl.t
@@ -1,6 +1,7 @@
 echo "definition lists"
 
 rc=0
+MARKDOWN_FLAGS=
 
 SEP='
 =this=
diff --git a/tests/emphasis.t b/tests/emphasis.t
index c0f7370..c4ebc59 100644
--- a/tests/emphasis.t
+++ b/tests/emphasis.t
@@ -1,6 +1,7 @@
 echo "emphasis"
 
 rc=0
+MARKDOWN_FLAGS=
 
 echo -n '  *hi* -> <em>hi</em> .............. '
 
diff --git a/tests/flow.t b/tests/flow.t
index acff704..32fb450 100644
--- a/tests/flow.t
+++ b/tests/flow.t
@@ -1,6 +1,7 @@
 echo "paragraph flow"
 
 rc=0
+MARKDOWN_FLAGS=
 
 echo -n '  header followed by paragraph ..... '
 
diff --git a/tests/html.t b/tests/html.t
index 3191b6b..77ab3c8 100644
--- a/tests/html.t
+++ b/tests/html.t
@@ -1,6 +1,7 @@
 echo "html blocks"
 
 rc=0
+MARKDOWN_FLAGS=
 
 echo -n '  self-closing block tags (hr) ..... '
 
diff --git a/tests/linkylinky.t b/tests/linkylinky.t
index da7e452..9dd8079 100644
--- a/tests/linkylinky.t
+++ b/tests/linkylinky.t
@@ -1,6 +1,7 @@
 echo "embedded links"
 
 rc=0
+MARKDOWN_FLAGS=
 
 echo -n '  url contains & ................... '
 
diff --git a/tests/list.t b/tests/list.t
index 3f78f17..97cee73 100644
--- a/tests/list.t
+++ b/tests/list.t
@@ -1,6 +1,7 @@
 echo "lists"
 
 rc=0
+MARKDOWN_FLAGS=
 
 echo -n '  two separated items (1) .......... '
 
diff --git a/tests/misc.t b/tests/misc.t
index fd7efa1..a52cf69 100644
--- a/tests/misc.t
+++ b/tests/misc.t
@@ -1,6 +1,7 @@
 echo "misc"
 
 rc=0
+MARKDOWN_FLAGS=
 
 echo -n '  single paragraph ................. '
 
diff --git a/tests/pandoc.t b/tests/pandoc.t
index 5daccc7..a4d9825 100644
--- a/tests/pandoc.t
+++ b/tests/pandoc.t
@@ -1,6 +1,7 @@
 echo "pandoc headers"
 
 rc=0
+MARKDOWN_FLAGS=
 
 if ./markdown -V | grep HEADER > /dev/null; then
 
@@ -18,6 +19,20 @@ if ./markdown -V | grep HEADER > /dev/null; then
 	rc=1
     fi
 
+    echo -n '  valid header with -F0x0100........ '
+    TEXT='% title
+% author(s)
+% date
+'
+    count=`echo "$TEXT" | ./markdown -F0x0100 | grep title | wc -l`
+
+    if [ "$count" -gt 0 ]; then
+	echo "ok"
+    else
+	echo "FAILED"
+	rc=1
+    fi
+
     echo -n '  invalid header ................... '
     TEXT='% title
 % author(s)
diff --git a/tests/smarty.t b/tests/smarty.t
index df8a2be..e365a03 100644
--- a/tests/smarty.t
+++ b/tests/smarty.t
@@ -1,6 +1,7 @@
 echo "smarty pants"
 
 rc=0
+MARKDOWN_FLAGS=
 
 MARKDOWN_FLAGS=0x0; export MARKDOWN_FLAGS