`hexyl /dev/zero` hangs about hexyl HOT 6 CLOSED

What do you expect the behavior to be in this instance?

from hexyl.

What do you expect the behavior to be in this instance?

Anything but empty output, which makes it impossible to tell if anything is happening at all.

1. Spitting out a bunch of zeroes as xxd does. But I guess it goes against the design of hexyl.
2. The zeroes before the skipped part. Let me explain.

dd if=/dev/zero count=5000B | hexyl

outputs

┌────────┬─────────────────────────┬─────────────────────────┬────────┬────────┐
│00000000│ 00 00 00 00 00 00 00 00 ┊ 00 00 00 00 00 00 00 00 │⋄⋄⋄⋄⋄⋄⋄⋄┊⋄⋄⋄⋄⋄⋄⋄⋄│
│*       │                         ┊                         │        ┊        │
│00001380│ 00 00 00 00 00 00 00 00 ┊                         │⋄⋄⋄⋄⋄⋄⋄⋄┊        │
└────────┴─────────────────────────┴─────────────────────────┴────────┴────────┘

so it would be cool if

hexyl /dev/zero

printed

┌────────┬─────────────────────────┬─────────────────────────┬────────┬────────┐
│00000000│ 00 00 00 00 00 00 00 00 ┊ 00 00 00 00 00 00 00 00 │⋄⋄⋄⋄⋄⋄⋄⋄┊⋄⋄⋄⋄⋄⋄⋄⋄│
│*       │                         ┊                         │        ┊        │

and then hanged. So yeah, basically just flushing the output after the * row.

from hexyl.

So yeah, basically just flushing the output after the * row.

Agreed. This is also what hexdump -C and xxd -a (-a = autoskip = squeezing) do.

Thank you for reporting this.

from hexyl.

Great, I'll look into fixing this today.

from hexyl.

It looks like the issue is a simple one-liner: the write buffer isn't flushed until the very end of output. I wrote it this way initially to mitigate performance issues from flushing the buffer, but benchmarks show that the effect is negligible. I've added a line that will flush after every line.

from hexyl.

It looks like the issue is a simple one-liner: the write buffer isn't flushed until the very end of output. I wrote it this way initially to mitigate performance issues from flushing the buffer, but benchmarks show that the effect is negligible. I've added a line that will flush after every line.

Thank you very much for looking into this! Any chance you could share those benchmark results? I also would have expected repeated flush calls for every line to be performance-relevant.

from hexyl.