seodisparate

2년 전discuss

One can use C's `cleanup` attribute like a defer. https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attribute...

The function signature is `void(MyType*)` if it is used like:

    __attribute__((cleanup(MyTypeCleanupFunction)))
    MyType myType;

If it's a pointer, it'll call the cleanup as a double ptr, and etc. Note that the specified cleanup function can do anything you want to, though the intended purpose is to cleanup the variable when it goes out of scope.

seodisparate

2년 전discuss

Or using .ssh/config since entries in there act like hostnames:

    # ~/.ssh/config
    Host github_ssh
        HostName github.com
        User git
        IdentityFile ~/.ssh/my_github_key

    > git remote add github github_ssh:Username/RepoName.git

This has worked reliably for me for quite a while now.

seodisparate

2년 전discuss

Reminds me of https://goshdarnfunctionpointers.com/ which has helped in some cases.

seodisparate

3년 전discuss

Isn't there `proc` on Linux systems?

Get the pid of the process you want to inspect, and while its running, execute `ls -lh /proc/<pid>/fd/`. It will list the open file descriptors for that process.

seodisparate

3년 전discuss

One could use `printf 'first\0second'` in the Bash shell as an example of making a "string" with null embedded into it, but you can't store that in a Bash variable.

    $ TEST_VAR="$(printf 'first\0second')"
    bash: warning: command substitution: ignored null byte in input

I'm not familiar with working with null characters in Bash in this way, but I think there might be a way to do it.

seodisparate

3년 전discuss

Similarly, I have a somewhat simple demo made for my website that is C++/Emscripten/Raylib. It's open source (MIT License) and you can grok the code here https://git.seodisparate.com/stephenseo/jumpartifact.com_dem... and check out the demo itself from the link within that page.

seodisparate

3년 전discuss

https://choosealicense.com/ is a good resource that lists a bunch of licenses explained.

seodisparate

3년 전discuss

I made a C++ project[1] (using OpenCL and blue noise) to generate dithered images/video for a course project (the course taught how to program for the GPU). If anyone wants to just jump straight into generating dithered images, you can try it out yourself. (It only works if OpenCL is configured for your system. It works on my desktop with a GPU and does not work on my laptop without a separate GPU.)

EDIT: Oh right, it also requires FFmpeg to be installed as it uses it. And libpng. And CMake. And PkgConfig.

[1]: https://github.com/Stephen-Seo/EN605.617.81.FA21_StephenSeo_...

seodisparate

4년 전discuss

You can use a GPG key stored on a YubiKey with openssh, but with some caveats:

1. gpg-agent must act as your ssh-agent (which means ssh-agent should be disabled and replaced by gpg-agent).

2. If using `pinentry-curses` (YubiKey usually permits access to the contained GPG key via the use of a pin), you must have `export GPG_TTY=$(tty)` (or your shell's equivalent of setting the GPG_TTY environment value to the output of `tty`).

3. You can fetch the public key of your GPG key with `ssh-add -L` (gpg-agent must be acting as your ssh-agent, and the YubiKey with the GPG key has to be plugged in).

4. You must have the line `enable-ssh-support` in your `$GNUPGHOME/gpg-agent.conf`.

I used a guide[1] to set up a GPG key on to a YubiKey, and for those who don't want to use GPG, the guide also has a section[2] about just using an SSH key as well.

[1]: https://github.com/drduh/YubiKey-Guide

[2]: https://github.com/drduh/YubiKey-Guide#ssh

seodisparate

4년 전discuss

[1] discusses firejail running as root:

> For a server, the process exposed to the outside world runs as an unprivileged user (unbound or nobody). The process is started by a separate process running as root (as explained by @Ferroin above). The starting process is never exposed to outside.

> The same is true for Firejail. By the time the unprivileged server process starts, Firejail is already sleeping.

And I think Docker has a similar problem as mentioned in the "warning" section in [2]:

> Warning: Anyone added to the docker group is root equivalent because they can use the docker run --privileged command to start containers with root privileges. For more information see [3] and [4].

[1]: https://github.com/netblue30/firejail/issues/1720

[2]: https://wiki.archlinux.org/title/Docker#Installation

seodisparate

4년 전discuss

As a lightweight alternative to Docker-based (or any container-based) solutions: Try firejail. You can set up a directory that will be the "home" of the sandboxed application you're running, then you can do something like `firejail --private="${HOME}/my_firefox_jail" firefox`. There are built-in profiles for many applications already, and you can customize them (by adding `.local` files, not editing the existing `.profile` files). See the following link for details.

https://wiki.archlinux.org/title/Firejail

seodisparate

4년 전discuss

Someone else on HN earlier posted their QR-code scanning Android app[1], which I've been using because it doesn't automatically follow URLs but displays the raw text of the QR code. It's been helpful for me, especially when I've been setting up QR codes for a new wireless router.

[1]: https://github.com/prof18/Secure-QR-Reader

seodisparate

4년 전discuss

Is it too old-fashioned of me to prefer IRC? Discord has its place, but I favor IRC.

seodisparate

4년 전discuss

I use the `rustup` package instead of the `rust` package to manage a local installation of rust. This graph seems to show installations of the `rust` package, but I don't think that accounts for `rustup`. `rustup` is recommended on Rust's own website ( https://www.rust-lang.org/learn/get-started ) and some users may have installed `rustup` via the bootstrap script instead of from Arch's own package repository. So I guess there's some additional variables that may not be accounted for regarding `rust`.

EDIT: Try this: https://pkgstats.archlinux.de/compare/packages#packages=dmd,...

seodisparate

4년 전discuss

Been using Linode since 2019. Service worked as expected (worked well), and I hope that won't change after this. If I had to move, I'd have to go through the pain of setting up my website(s) again, but at least I have backups, so it's just a matter of time spent getting set up again..

seodisparate

5년 전discuss

As someone with a C/C++ background, this gist was a good reference for those times I needed to use Javascript: https://gist.github.com/yig/8744917

seodisparate

5년 전discuss

Oh I see, thanks for the reply. I did a quick search and came upon https://blog.cloudflare.com/encrypted-client-hello/ which does shed light on ECH. Though I am not sure if only Cloudflare-backed servers provide ECH, or if it is even available. Seems relatively new.

EDIT: Ah, the blog post does indicate that ECH is a work in progress.

seodisparate

5년 전discuss

Out of curiosity, I once used wireshark to examine packets from my own system which was configured to use DNS over HTTPS (using dnscrypt-proxy). I discovered that the hostname of the server is in plaintext in a header of a packet separate of the DNS query packets. I think this is due to verification of HTTPS certs, but not sure. By what I've discovered, AFAIK that to completely obscure the server's hostname from the currently used ISP, a VPN (or proxy) is probably necessary.

seodisparate

5년 전discuss

Redox-OS has a similar situation that kernel code should never panic https://gitlab.redox-os.org/redox-os/redox/blob/master/CONTR... .

    No possible panics should ever exist in kernel space, because then the whole OS would just stop working.

Note that Redox-OS is written completely in Rust.

seodisparate

6년 전discuss

In Korean, the vowels ㅣ (ee sound) and ㅐ (eh sound) are different in the written language. There are actually more difficult things such as ㅐ and ㅔ (both "eh" sound) which can get confusing when trying to spell Korean words. In practice, I personally don't get confused differentiating between "nee-gah" and "ne-gah", but that may have been due to me having Korean parents and being used to that terminology since birth.

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