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Comment by twic

1 day ago

Not sure if this is related, but i'd love to see more scripting languages (mostly Python) offer facilities which let them take over from shell script for more scripts and one-liners.

Think about what it would take to write this in Python right now:

  for wmv_file in $(find $1 -name '*.wmv'); do
    echo -n "${wmv_file} "
    ffmpeg -i $wmv_file ${wmv_file%.wmv}.mpg 2>&1 | grep kb/s: || echo "ERROR $?"
  done

With a few handy variables and functions predefined, this could be something like:

  for wmv_file in find(argv[1], glob="\*.wmv"):
    print(wmv_file, end=" ")
    result = do("ffmpeg", "-i", wmv_file, basename(wmv_file, ".wmv") + ".mpg")
    if result: print(grep(str(result), "kb/s:"))
    else: print("ERROR", result.status)

7 comments

twic

Reply
empthought  1 day ago

How about

  for wmv in Path(sys.argv[1]).rglob("\*.wmv"):
        print(wmv, end=" ")
        r = subprocess.run(
            ["ffmpeg", "-i", wmv, wmv.with_suffix(".mpg")],
            stdout=subprocess.PIPE, stderr=subprocess.STDOUT,
        )
        lines = [l for l in r.stdout.decode().splitlines() if "kb/s:" in l]
        print("\n".join(lines) if lines else f"ERROR {r.returncode}")

?

If you go outside stdlib you can use the sh library instead of subprocess.run.

  • twic  8 hours ago

    Not bad, but the subprocess invocation is too verbose given this is a staple of shell script type work, and the string mangling is a bit painful.

MarsIronPI  1 day ago

Ruby does a pretty good job, with `system` and backticks. The FileUtils module actually defines some nice helpers like `mv`, `cp` and `ln_s`. So you can do `cp "/tmp/a.txt", filename`. And you can get a list of files matching a glob with `Dir["/tmp/*.txt"]`.