Dir.glob("/<path_to_dir>/current_*").map{ |file| File.readlink(file) if File.symlink?(file) }.compact
Explanation:
Dir.glob("/<path_to_dir>/current_*") # Matches all files beginning with current_ in the specified path
Dir.glob("/<path_to_dir>/*current_") # Matches all files ending with current_ in the specified path
Dir.glob("/<path_to_dir>/*current_*") # Match all files that have c in them (including at the beginning or end) in the specified path
.map { |file| # iterates and pushes result into array
File.readlink(file) if File.symlink?(file) # Get the target file if the file is a symlink
}.compact # if the file is not a symlink in the specified path, map fills nil by default. Using compact at the end removes all nil entries from the resulting array and gives you only symlink target files in an array.
UPDATE:
OP wanted only the filename for that we should be using File.basename(File.readlink(file))