+sub check_executable($$) {
+ # (GnuPG::Interface gives lousy errors when the gpg binary isn't found,
+ # so we want to check manually.)
+ my ($purpose, $fn) = @_;
+ # Only check provided fnames with a slash in them.
+ return unless defined $fn;
+ if ($fn =~ m!/!) {
+ die ("$PROGRAM_NAME: $purpose executable '$fn' not found.\n") unless -x $fn;
+ } else {
+ for my $p (split(':', $ENV{PATH})) {
+ return if -x "$p/$fn";
+ };
+ die ("$PROGRAM_NAME: $purpose executable '$fn' not found on path.\n") unless -x $fn;
+ };
+};
+