directory-listing-before-filename-regexp

directory-listing-before-filename-regexp is a variable defined in `files.el'.
Its value is

"\\([0-9][BkKMGTPEZY]? \\(\\([0-9][0-9][0-9][0-9]-\\)?[01][0-9]-[0-3][0-9][ T][ 0-2][0-9][:.][0-5][0-9]\\(:[0-6][0-9]\\([.,][0-9]+\\)?\\( ?[-+][0-2][0-9][0-5][0-9]\\)?\\)?\\|[0-9][0-9][0-9][0-9]-[01][0-9]-[0-3][0-9]\\)\\|.*[0-9][BkKMGTPEZY]? \\(\\(\\([A-Za-z']\\|[^-]\\)\\([A-Za-z']\\|[^-]\\)+\\.? +[ 0-3][0-9]\\|[ 0-3][0-9]\\.? \\([A-Za-z']\\|[^-]\\)\\([A-Za-z']\\|[^-]\\)+\\.?\\) +\\([ 0-2][0-9][:.][0-5][0-9]\\|[0-9][0-9][0-9][0-9]\\)\\|\\([A-Za-z']\\|[^-]\\)\\([A-Za-z']\\|[^-]\\)+\\.? +[ 0-3][0-9], +[0-9][0-9][0-9][0-9]\\|\\([ 0-1]?[0-9]\\([A-Za-z]\\|[^-]\\)? [ 0-3][0-9]\\([A-Za-z]\\|[^-]\\)? +\\|[ 0-3][0-9] [ 0-1]?[0-9] +\\)\\([ 0-2][0-9][:.][0-5][0-9]\\|[0-9][0-9][0-9][0-9]\\([A-Za-z]\\|[^-]\\)?\\)\\)\\) +"

Documentation:
Regular expression to match up to the file name in a directory listing.
The default value is designed to recognize dates and times
regardless of the language.