diff --git a/ikiwiki-comment.in b/ikiwiki-comment.in
index b0cea4a4a..8f3db8988 100755
--- a/ikiwiki-comment.in
+++ b/ikiwiki-comment.in
@@ -9,44 +9,74 @@ sub usage () {
 	die gettext("usage: ikiwiki-comment pagefile"), "\n";
 }
 
-my $pagefile=shift || usage ();
+sub main {
+	my $pagefile=shift || usage ();
+	my $dir=get_dir($pagefile);
+	my $page=get_page($pagefile);
 
-my $dir=IkiWiki::dirname($pagefile);
-$dir="." unless length $dir;
-my $page=IkiWiki::basename($pagefile);
-if (! -d $pagefile) {
-	$page=~s/\.[^.]+$//;
+	IkiWiki::Plugin::comments::checkconfig();
+	my $comment_num=1+IkiWiki::Plugin::comments::num_comments($page, $dir);
+
+	chomp(my $content = join('', <STDIN>)) unless -t STDIN;
+
+	my $comment=get_comment(get_username(), $comment_num, $content);
+
+	# This will yield a hash of the comment before it's edited,
+	# but that's ok; the date provides sufficient entropy to avoid collisions,
+	# and the hash of a comment does not need to match its actual content.
+	# Doing it this way avoids needing to move the file to a final
+	# location after it's edited.
+	my $location=IkiWiki::Plugin::comments::unique_comment_location($page, $comment, $dir)."._comment";
+
+	IkiWiki::writefile($location, $dir, $comment);
+	exec_editor("$dir/$location") if -t STDIN;
 }
 
-IkiWiki::Plugin::comments::checkconfig();
-my $comment_num=1 + IkiWiki::Plugin::comments::num_comments($page, $dir);
-
-my $username = getpwuid($<);
-if (! defined $username) { $username="" }
-
-my $comment="[[!comment format=mdwn\n";
-$comment.=" username=\"$username\"\n";
-$comment.=" subject=\"\"\"comment $comment_num\"\"\"\n";
-$comment.=" " . IkiWiki::Plugin::comments::commentdate() . "\n";
-$comment.=" content=\"\"\"\n\n\"\"\"]]\n";
-
-# This will yield a hash of the comment before it's edited,
-# but that's ok; the date provides sufficient entropy to avoid collisions,
-# and the hash of a comment does not need to match its actual content.
-# Doing it this way avoids needing to move the file to a final
-# location after it's edited.
-my $location=IkiWiki::Plugin::comments::unique_comment_location($page, $comment, $dir)."._comment";
-
-IkiWiki::writefile($location, $dir, $comment);
-
-my @editor="vi";
-if (-x "/usr/bin/editor") {
-	@editor="/usr/bin/editor";
+sub get_dir {
+	my ($file) = @_;
+	my $dir=IkiWiki::dirname($file);
+	$dir="." unless length $dir;
+	return $dir;
 }
-if (exists $ENV{EDITOR}) {
-	@editor=split(' ', $ENV{EDITOR});
+
+sub get_page {
+	my ($file) = @_;
+	my $page=IkiWiki::basename($file);
+	$page=~s/\.[^.]+$// unless -d $file;
+	return $page;
 }
-if (exists $ENV{VISUAL}) {
-@editor=split(' ', $ENV{VISUAL});
+
+sub get_username {
+	my $username = getpwuid($<);
+	$username="" unless defined $username;
+	return $username;
 }
-exec(@editor, "$dir/$location");
+
+sub get_comment {
+	my ($username, $comment_num, $content) = @_;
+	$content = '' unless defined $content;
+	my $comment="[[!comment format=mdwn\n";
+	$comment.=" username=\"$username\"\n";
+	$comment.=" subject=\"\"\"comment $comment_num\"\"\"\n";
+	$comment.=" " . IkiWiki::Plugin::comments::commentdate() . "\n";
+	$comment.=" content=\"\"\"\n$content\n\"\"\"]]\n";
+	return $comment;
+}
+
+sub exec_editor {
+	my ($file) = @_;
+
+	my @editor="vi";
+	if (-x "/usr/bin/editor") {
+		@editor="/usr/bin/editor";
+	}
+	if (exists $ENV{EDITOR}) {
+		@editor=split(' ', $ENV{EDITOR});
+	}
+	if (exists $ENV{VISUAL}) {
+	@editor=split(' ', $ENV{VISUAL});
+	}
+	exec(@editor, $file);
+}
+
+main(@ARGV);