+ return '^' . $in . "\$";
+}
+
+# read in a file into a string and return it.
+# the filename can be split into a dir and file and the
+# file can be in upper or lower case.
+# there can also be a suffix
+sub readfilestr
+{
+ my ($dir, $file, $suffix) = @_;
+ my $fn;
+ my $f;
+ if ($suffix) {
+ $f = uc $file;
+ $fn = "$dir/$f.$suffix";
+ unless (-e $fn) {
+ $f = lc $file;
+ $fn = "$dir/$file.$suffix";
+ }
+ } elsif ($file) {
+ $f = uc $file;
+ $fn = "$dir/$file";
+ unless (-e $fn) {
+ $f = lc $file;
+ $fn = "$dir/$file";
+ }
+ } else {
+ $fn = $dir;
+ }
+
+ my $fh = new IO::File $fn;
+ my $s = undef;
+ if ($fh) {
+ local $/ = undef;
+ $s = <$fh>;
+ $fh->close;
+ }
+ return $s;
+}
+
+# write out a file in the format required for reading
+# in via readfilestr, it expects the same arguments
+# and a reference to an object
+sub writefilestr
+{
+ my $dir = shift;
+ my $file = shift;
+ my $suffix = shift;
+ my $obj = shift;
+ my $fn;
+ my $f;
+
+ confess('no object to write in writefilestr') unless $obj;
+ confess('object not a reference in writefilestr') unless ref $obj;
+
+ if ($suffix) {
+ $f = uc $file;
+ $fn = "$dir/$f.$suffix";
+ unless (-e $fn) {
+ $f = lc $file;
+ $fn = "$dir/$file.$suffix";
+ }
+ } elsif ($file) {
+ $f = uc $file;
+ $fn = "$dir/$file";
+ unless (-e $fn) {
+ $f = lc $file;
+ $fn = "$dir/$file";
+ }
+ } else {
+ $fn = $dir;
+ }
+
+ my $fh = new IO::File ">$fn";
+ if ($fh) {
+ my $dd = new Data::Dumper([ $obj ]);
+ $dd->Indent(1);
+ $dd->Terse(1);
+ $dd->Quotekeys(0);
+ # $fh->print(@_) if @_ > 0; # any header comments, lines etc
+ $fh->print($dd->Dumpxs);
+ $fh->close;
+ }
+}
+
+sub filecopy
+{
+ copy(@_) or return $!;
+}
+
+# remove leading and trailing spaces from an input string
+sub unpad
+{
+ my $s = shift;
+ $s =~ s/\s+$//;
+ $s =~ s/^\s+//;
+ return $s;
+}
+
+# check that a field only has callsign characters in it
+sub is_callsign
+{
+ return $_[0] =~ m!^
+ (?:(?:[A-Z]{1,2}\d* | \d[A-Z]{1,2}\d*)/)? # out of area prefix /
+ (?:[A-Z]{1,2}\d+ | \d[A-Z]{1,2}\d+)? # main prefix one
+ [A-Z]{1,5} # callsign letters
+ (?:-\d{1,2})? # - nn possibly (eg G8BPQ-8)
+ (?:/[0-9A-Z]{1,7})? # / another prefix, callsign or special label (including /MM, /P as well as /EURO or /LGT) possibly
+ $!x;
+
+ # longest callign allowed is 1X11/1Y11XXXXX-11/XXXXXXX
+}
+
+sub is_prefix
+{
+ return $_[0] =~ m!^(?:[A-Z]{1,2}\d+ | \d[A-Z]{1,2}}\d+)!x # basic prefix