this post was submitted on 15 May 2024
882 points (98.5% liked)

linuxmemes

21453 readers
1920 users here now

Hint: :q!

Sister communities:

Community rules (click to expand)

1. Follow the site-wide rules

2. Be civil
  • Understand the difference between a joke and an insult.
  • Do not harrass or attack members of the community for any reason.
  • Leave remarks of "peasantry" to the PCMR community. If you dislike an OS/service/application, attack the thing you dislike, not the individuals who use it. Some people may not have a choice.
  • Bigotry will not be tolerated.
  • These rules are somewhat loosened when the subject is a public figure. Still, do not attack their person or incite harrassment.
    • 3. Post Linux-related content
  • Including Unix and BSD.
  • Non-Linux content is acceptable as long as it makes a reference to Linux. For example, the poorly made mockery of sudo in Windows.
  • No porn. Even if you watch it on a Linux machine.
    • 4. No recent reposts
  • Everybody uses Arch btw, can't quit Vim, and wants to interject for a moment. You can stop now.
    •  

    Please report posts and comments that break these rules!

    Important: never execute code or follow advice that you don't understand or can't verify, especially here. The word of the day is credibility. This is a meme community -- even the most helpful comments might just be shitposts that can damage your system. Be aware, be smart, don't fork-bomb your computer.

    founded 1 year ago
    MODERATORS
    poopsmith
    zephyr
    rtxn
    882
    Old XKCD, still relevant (lemmy.dbzer0.com)
    submitted 6 months ago by [email protected] to c/linuxmemes
    156 comments fedilink hide all child comments
     

    Was trying to extract a totally legit copy of Skate 3 I downloaded today to play on my Steam Deck

    you are viewing a single comment's thread
    view the rest of the comments
    [–] [email protected] 5 points 6 months ago (1 children)

    Yes. However, if you had skipped the -f, it would have been valid. Without the filename argument, it assumes it should extract from the tape drive (TAR = Tape ARchive). The tape device is probably something like /dev/rmt0, but you don't need to specify that. Using the -f is technically an exception which means "instead of extracting from the tape like you'd normally do, pretend that this file is the tape device instead."

    [–] [email protected] 3 points 6 months ago* (last edited 6 months ago) (1 children)

    GNU tar, at least a modern one, that is the one that happens to come with my system, won't try to read from /dev but stdin and then complain that it's a terminal and refuse.

    Quoth POSIX on the f flag:

    Use the first file operand [...] as the name of the archive instead of the system-dependent default.

    That is GNU is compliant, here, the default is system-dependent. f - is required to be stdin, though, so you can bunzip2 foo.tar.bz2 | tar xf - or such in a portable manner, don't have to rely on tar having a z option (which is nonstandard) or it auto-detecting compression (even more nonstandard). What is not standard either is tar -x: Tar doesn't take leading hyphens. Tar is one of those programs so old its command line syntax got standardised before command line syntax standards were established. OTOH it's not nearly as bad as dd, you can interpret how tar does things in the same way as git pull: It's a subcommand, not a flag.

    [–] [email protected] 1 points 6 months ago (1 children)

    "one of those programs so old its...syntax got standardized before command line syntax standards were established." --This is wild to learn, but also confusing. How does tar not take leading hyphens, but I've only ever used it as such without error of any kind? Not even bragging I've been doing that for 10+ years too lol

    [–] [email protected] 2 points 6 months ago* (last edited 6 months ago)

    Hmm. Actually you prompted me to dig a bit deeper: tar goes all the back to Version 7 UNIX, 1979, but the command line syntax is shared with tap, included in Version 1, man page dated to 1971-11-03. Development of C started 1972. Might've been written in B, you'd have to unearth a source archive I bet it's around somewhere. But anyway if you look through the other Version 1 commands a lot of them don't take hyphen commands, ls does, e.g. rm doesn't on account of only taking file names as arguments.

    dd is actually younger, Version 5, 1974, the syntax apparantly comes from IBM's JCL.

    Admittedly, that's all before my time.

    Both BSD and GNU tar take hyphens, I don't really have any experience with anything else but a short stint with Solaris in the early 2000s (very emphatically before Sun got gobbled up by Oracle) and I don't remember hyphens tripping me up. Much unlike killall. And I'm apparently not alone in that.