Global symbol "$file" requires explicit package name at ./backup.pl line 9.
Global symbol "$file" requires explicit package name at ./backup.pl line 11.
Global symbol "@columns" requires explicit package name at ./backup.pl line 18.
Global symbol "@columns" requires explicit package name at ./backup.pl line 20.
Global symbol "@columns" requires explicit package name at ./backup.pl line 21.
Global symbol "@columns" requires explicit package name at ./backup.pl line 22.
Global symbol "@columns" requires explicit package name at ./backup.pl line 23.
Global symbol "@columns" requires explicit package name at ./backup.pl line 24.
Global symbol "@columns" requires explicit package name at ./backup.pl line 25.
Global symbol "@columns" requires explicit package name at ./backup.pl line 26.
Execution of ./backup.pl aborted due to compilation errors.