См. man run-parts. В нем сказано:
NAME
run-parts - run scripts or programs in a directory
SYNOPSIS
run-parts [--test] [--verbose] [--report] [--lsbsysinit] [--regex=RE] [--umask=umask] [--arg=argument] [--exit-on-error] [--help] [--version] [--list]
[--reverse] [--] DIRECTORY
run-parts -V
DESCRIPTION
run-parts runs all the executable files named within constraints described below, found in directory directory. Other files and directories are silently
ignored.