#networking #cli #utilization

app what

Display current network utilization by process, connection and remote IP/hostname

12 releases (4 breaking)

0.5.1 Dec 23, 2019
0.5.0 Dec 22, 2019
0.4.1 Dec 20, 2019
0.3.7 Nov 12, 2019
0.1.0 Oct 17, 2019

#1921 in Network programming

49 downloads per month

MIT license

1.5K SLoC


...is taking up my bandwidth?!


This is a CLI utility for displaying current network utilization by process, connection and remote IP/hostname

How does it work?

what sniffs a given network interface and records IP packet size, cross referencing it with the /proc filesystem on linux or lsof on MacOS. It is responsive to the terminal window size, displaying less info if there is no room for it. It will also attempt to resolve ips to their host name in the background using reverse DNS on a best effort basis.


Arch Linux

yay -S what

MacOS and other Linux flavours

cargo install what

If you're on linux, you could also get the generic binary from the releases.

Windows is not supported at the moment - if you'd like to contribute a windows port, it would be very much welcome.


    what [FLAGS] [OPTIONS]

    -h, --help          Prints help information
    -n, --no-resolve    Do not attempt to resolve IPs to their hostnames
    -r, --raw           Machine friendlier output
    -V, --version       Prints version information

    -i, --interface <interface>    The network interface to listen on, eg. eth0

Note that since what sniffs network packets, it requires root privileges - so you might want to use it with (for example) sudo.


what also supports an easier-to-parse mode that can be piped or redirected to a file. For example, try:

what --raw | grep firefox


Contributions of any kind are very welcome. If you'd like a new feature (or found a bug), please open an issue or a PR.

To set up your development environment:

  1. Clone the project
  2. cargo run, or if you prefer cargo run -- -i <network interface name> (you can often find out the name with ifconfig or iwconfig). You might need root privileges to run this application, so be sure to use (for example) sudo.

To run tests: cargo test

Note that at the moment the tests do not test the os layer (anything in the os folder).

If you are stuck, unsure about how to approach an issue or would like some guidance, you are welcome to contact: aram@poor.dev




~344K SLoC