Cat log-rotated log files passed as arguments in the right order, unpacking them with zcat, bzcat or xzcat if necessary.

zzcat

#!/usr/bin/env python3
"""
Cat log-rotated log files passed as arguments in the right order, unpacking
them with zcat, bzcat or xzcat if necessary.
"""
import argparse
import os
import subprocess
import sys


ARCHIVE_CATS = {
    "gz": "zcat",
    "bz2": "bzcat",
    "xz": "xzcat",
}


def get_log_order(filename):
    lst = filename.split(".")
    if lst[-1] in ARCHIVE_CATS:
        del(lst[-1])
    try:
        # Return a negative value, so that foo.log.2 is sorted *before*
        # foo.log.1
        return -int(lst[-1])
    except ValueError:
        # Not a number, assume this is foo.log
        return 0


def cat(filename):
    ext = os.path.splitext(filename)[1]
    cat_cmd = ARCHIVE_CATS.get(ext[1:], "cat")
    subprocess.run([cat_cmd, filename])


def main():
    parser = argparse.ArgumentParser()
    parser.description = __doc__

    parser.add_argument("files", nargs="+")

    args = parser.parse_args()
    files = sorted(args.files, key=get_log_order)
    for file in files:
        cat(file)

    return 0


if __name__ == "__main__":
    sys.exit(main())
# vi: ts=4 sw=4 et

Thanks for sharing.
I am curious how many lines it would be as a shell script?
Any volunteer for a language contest? :-)

Probably less, but this one could be less lines if it were not pep8 compliant and did not have a proper argument parser... (yes, this thing supports -h and --help). I usually give up on shell scripts when it's time to do arithmetic, but give it a try, I am curious to see what you come up with :)