Allow the empty string in wallet-backend arguments.

When writing to a file in the wallet client program, remove an old
backup file before creating a new backup and don't fail if the backup
already exists.

1 files changed, 1 insertions, 1 deletions

diff --git a/server/wallet-backend b/server/wallet-backend
index c2be5e7..4af7490 100755
--- a/server/wallet-backend
+++ b/server/wallet-backend
@@ -120,7 +120,7 @@ sub check_args {
     my %exclude = map { $_ => 1 } @$exclude;
     for (my $i = 1; $i <= @args; $i++) {
         next if $exclude{$i};
-        unless ($args[$i - 1] =~ m,^[\w_/.-]+\z,) {
+        unless ($args[$i - 1] =~ m,^[\w_/.-]*\z,) {
             error "invalid characters in argument: $args[$i - 1]";
         }
     }