• MoSal@programming.dev
    link
    fedilink
    arrow-up
    10
    ·
    18 days ago

    I didn’t realize this was posted here.

    Allow me to copy my comment from another thread:


    // Don't bail on the first error, but remember the worst one.
    let mut worst = 0;
    for file in files {
        if let Err(e) = chmod_one(file) {
            worst = worst.max(e.exit_code());
        }
    }
    process::exit(worst);
    

    This is not rustic, I feel.

    files.iter()
      .map(chmod_one)
      .filter_map(Result::err)
    

    is more like it.

    From there, you can next() for first error, last() for last error, or fold() for max error, or collect() if you need to save all errors.


    And no, static compilation doesn’t help here, because get_user_by_name goes through NSS, which dlopens libnss_* modules at runtime regardless of whether your binary is statically linked.

    This is not true in musl systems. I just quickly checked in a Chimera rootfs (which has a system dynamic musl libc btw).

    I believe the described dlopening is one of the well known reasons why GNU libc is not suitable for static linking, unlike musl!

    In Arch, this indeed loads /usr/lib/libnss_systemd.so.2.

    Everyone can test this with strace id 2>&1 | egrep 'open.*\.so'.

    • Bazebara@programming.dev
      link
      fedilink
      arrow-up
      1
      arrow-down
      1
      ·
      18 days ago

      In that for, all error messages have been lost. If to add such output “for” is the most elegant solution.

        • Bazebara@programming.dev
          link
          fedilink
          arrow-up
          1
          ·
          2 days ago

          The usual handling in Rust afterwards is in most cases log one error or return to upstream “there was an error”. In some rare cases all errors returned as a single case.

          Both of these first are bad for i18n and finding what’s really happened in the middle.