# w

Drop-in replacement for `w(1)` on systems with **procps-ng 4.x**.

## Problem

procps-ng 4.0 rewrote `w` to read from `/proc` instead of utmp, but
the process→session→tty mapping is broken. On a typical SSH login you get:

```
USER     TTY      FROM             LOGIN@   IDLE   JCPU   PCPU  WHAT
andreas           192.168.10.11    12:52    2:17   0.00s   ?    sshd: andreas [priv]
andreas           192.168.10.11    12:52    2:17   0.00s   ?    sshd: andreas [priv]
```

Three bugs in one:

| Column | Bug | Root cause |
|--------|-----|------------|
| TTY    | blank | utmp never read |
| IDLE   | same for everyone | can't stat the tty without knowing its name |
| WHAT   | shows `sshd: [priv]` | picks the SSH privilege-separation parent instead of the user's shell |

## Solution

This script reads the right sources directly:

- **utmp** via `who -u` — correct TTY name, login time, source host
- **`/dev/<tty>` atime** — real idle time
- **`/proc/pid/stat` `tpgid` field** — kernel's own record of each tty's
  foreground process group, used for JCPU/PCPU/WHAT (no `TIOCGPGRP` ioctl
  needed, which would fail on terminals we don't own anyway)

## Example output

```
13:07:07 up 15 min,  3 users,  load average: 0.05, 0.10, 0.09
USER       TTY      FROM             LOGIN@  IDLE   JCPU    PCPU    WHAT
andreas    pts/0    192.168.10.11    12:52   1:54   0.0s    0.0s    -bash
andreas    pts/1    192.168.10.11    12:52   0s     37.5s   37.5s   claude
stephan    pts/2    192.168.10.165   13:02   1s     0.0s    0.0s    -bash
```

## Install

```sh
cp w ~/bin/w
chmod +x ~/bin/w
```

Make sure `~/bin` appears before `/usr/bin` in your `PATH`.

## Requirements

Python 3.6+, `who`, `uptime` — all standard on any Linux system.
Tested on Ubuntu 24.04 (Noble) with procps-ng 4.0.4.