crc32sum - Calculate CRC32 for each file (Bash using 7z)

crc32sum

#!/usr/bin/env bash

if [[ "${#}" -eq 0 ]] || [[ "${1}" == '-h' ]]; then
    self="${0##*/}"
    cat <<EOF
usage: ${self} files...

Calculate CRC32 for each file.

positional arguments:
  file or dir       one or multiple file names or paths, if this is a directory
                    then traverse it recursively to find all files
EOF
    exit 0
fi

7z h -bsp2 -- "${@}" |
    \grep -v -E '^[ \t]+.*/' |
    \sed -n -e '/^-------- -------------  ------------$/,$p' |
    \sed '1d' |
    \grep --before-context "9999999" '^-------- -------------  ------------$' |
    \head -n -1 |
    \awk '$2=""; {print $0}'

The initial version of this script was actually broken. It would not output all files if a directory was included (wrong counting of files through argument number). Also filenames that contained a space would only output the first part until the space character.

All of this rookie mistakes are solved. Plus there is a progress bar showing what files are processed at the moment, instead showing a blank screen until command is finished. This is useful if there are a lot of files or some big files to process.