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Comment by chjj | Hacker News Reader

Now I'm wondering why ldd doesn't offer this feature in the first place.

The output format isn't nice, but LD_DEBUG=files will tell you which file requested each library.

(The LD_DEBUG environment option is a useful tool in the rare circumstances when you really, really need help debugging the library loading process.)

Because it's a core Linux tool and they basically never change. Why doesn't ps have an option to only show your processes? Why doesn't objdump tell you what all the symbol flags mean so I don't have to look them up on StackOverflow every time?

I'm sure there are better examples but there are a ton of ways the usability of the Linux CLI could be improved but nobody is going to bother because everything's written in horrible C and to contribute you'd have to join some mailing list and convince a load of stuck-in-the-mud it-was-hard-for-me-so-I'm-not-making-it-easy-for-you neckbeards that your change won't break compatibility on a PDP-11, and anyway what's the problem? You just run `ps -fu $(whoami) | less`. Easy.

Way easier and more fun to write a new tool.

> Why doesn't ps have an option to only show your processes?

Because that is the default behavior.

No, by default it shows you processes for the current terminal.

Only your processes for this terminal.

Yes. I meant "show me all my processes". A very common task that doesn't have a good solution.

Sure it does: “ps x” does that.

I agree that the interface of ps is awful with its two conflicting ways to define options, but `ps u` does show all your processes on Linux. I usually type `ps fux` to get a nice tree. Sadly that's Linux-specific and doesn't work on the Mac.

`ps u` just changes the output format. It's not the same as `ps -u $(whoami)`

You are right! I misremembered. It's `ps x`.

From `man ps`:

       x      Lift the BSD-style "must have a tty" restriction, which is imposed upon the set of all processes when some BSD-style (without "-") options are used or when the
              ps personality setting is BSD-like.  The set of processes selected in this manner is in addition to the set of processes selected by other means.  An alternate
              description is that this option causes ps to list all processes owned by you (same EUID as ps), or to list all processes when used together with the a option.

Trees are quite hard to do well in a CLI app. Everything from the Unicode drawing to the sizing to the color choices. This one looks great.

It's not like ldd is a paragon of cli design to begin with. Indentation isn't difficult, you just pass in the indentation level and increment as needed as you recursively walk the tree.

Unicode isn't necessary if the terminal supports ACS.

You can do a passable job with just + - and | if you need to. Have done that for a ucontroller's cli.

What is ACS?

Most terminals (even non-unicode-capable ones) offer a feature to switch into "alt charset mode" which provides glyphs for drawing lines.

Thanks! It’s getting rare to learn about a feature that surprises me, but I had no idea about this.

just saying: pstree figured it out

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