Overview

Here’s a simple script/function to keep n number of the latest files that match your argument(s) in the current directory. I wrote this in order to periodically clean rpm and deb repositories. It will create file lists by matching one or more input arguments and keep only the latest file from each list. The number of files to be kept for each matching list can be set using -k. The file can safely be sourced as a function.

Code

prunefiles:

#!/usr/bin/env bash
#
# prunefiles, a function to remove all but the n latest versions of a file
# by Bryan Roessler
#
# This file can be sourced directly to import `prunefiles` or run as a script
#
# Useful to prune rpm repositories of obsolete packages
#

declare -a _filePrefixes

prunefiles () {

    #############
    # DEFAULTS ##
    #############

    # Default number of matching files to keep
    _keepInt=1


    #############
    # FUNCTIONS #
    #############

    _printHelpAndExit () {

    cat <<-'EOF'
USAGE:
pruneFiles -k 3 thisfileprefix [thatfileprefix]

OPTIONS
    -k|--keep NUMBER
        Keep NUMBER of latest files that matches each file prefix (Default: 1)
EOF

    # Exit using passed exit code
    [[ -z $1 ]] && exit 0 || exit "$1"

}

    _parseInput () {

        if _input=$(getopt -o +k: -l keep: -- "$@"); then
            eval set -- "$_input"
            while true; do
                case "$1" in
                    -k|--keep)
                        shift && _keepInt=$1
                        ;;
                    --)
                        shift && break
                        ;;
                esac
                shift
            done
        else
            echo "Incorrect option(s) provided"
            _printHelpAndExit 1
        fi

        _filePrefixes=( "$@" )
    }


    _findAndRemove () {

        for _filePrefix in "${_filePrefixes[@]}"; do
            for _file in $(find . -maxdepth 1 -type f -name "${_filePrefix}*" -printf '%T@ %p\n' | sort -r -z -n | tail -n+$(($_keepInt + 1)) | awk '{ print $2; }'); do
                rm "$_file"
            done
        done
    }


    __main () {

        _parseInput "$@"
        _findAndRemove

    }

    __main "$@"
}

# Allow script to be safely sourced
if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
    prunefiles "$@"
    exit $?
fi

Example

$ ls
Package-25-1.rpm
Package-25-2.rpm
Package-25-3.rpm
Package-25-4.rpm
Package-26-1.rpm
Package-26-2.rpm
Package-27-1.rpm
Package-27-2.rpm
$ prunefiles Package-25 Package-27
$ ls
Package-25-4.rpm
Package-26-1.rpm
Package-26-2.rpm
Package-27-2.rpm

Conclusion

I have provided a prunefiles script/function that keeps n number of latest files in the current directory that match any number of input argument(s).