headers_install: use local file handles

Better practice to use 3 arg open and local file handles.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Acked-by: WANG Cong <amwang@redhat.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>

scripts/headers_install.pl

@@ -23,13 +23,13 @@ my ($readdir, $installdir, $arch, @files) = @ARGV;
 my $unifdef = "scripts/unifdef -U__KERNEL__ -D__EXPORTED_HEADERS__";
 
 foreach my $file (@files) {
-	local *INFILE;
-	local *OUTFILE;
 	my $tmpfile = "$installdir/$file.tmp";
-	open(INFILE, "<$readdir/$file")
+
+	open(my $in, '<', "$readdir/$file")
 	    or die "$readdir/$file: $!\n";
-	open(OUTFILE, ">$tmpfile") or die "$tmpfile: $!\n";
-	while (my $line = <INFILE>) {
+	open(my $out, '>', $tmpfile)
+	    or die "$tmpfile: $!\n";
+	while (my $line = <$in>) {
 		$line =~ s/([\s(])__user\s/$1/g;
 		$line =~ s/([\s(])__force\s/$1/g;
 		$line =~ s/([\s(])__iomem\s/$1/g;
@@ -39,10 +39,11 @@ foreach my $file (@files) {
 		$line =~ s/(^|\s)(inline)\b/$1__$2__/g;
 		$line =~ s/(^|\s)(asm)\b(\s|[(]|$)/$1__$2__$3/g;
 		$line =~ s/(^|\s|[(])(volatile)\b(\s|[(]|$)/$1__$2__$3/g;
-		printf OUTFILE "%s", $line;
+		printf {$out} "%s", $line;
 	}
-	close OUTFILE;
-	close INFILE;
+	close $out;
+	close $in;
+
 	system $unifdef . " $tmpfile > $installdir/$file";
 	unlink $tmpfile;
 }