Files by age, newest first:
ls -lt
Docker images by age, newest first:
docker images --format "{{.CreatedAt}}\t{{.Repository}}:{{.Tag}}" | sort -r
Files by size, largest first:
ls -lS
Docker images by size, largest first:
docker images --format "{{.Size}}\t{{.Repository}}:{{.Tag}}" | sort -rh
Why why why??!
Do you need a thread-safe atomic counter in Python? Use itertools.count():
>>> from itertools import count >>> counter = count() >>> next(counter) 0 >>> next(counter) 1 >>> next(counter) 2
I found this in the decorator package, labelled Atomic get-and-increment provided by the GIL
. So simple! So cool!
Need to redirect to a file from sudo? Use sudo tee >/dev/null:
$ sudo ls -l /root >/root/files.list -bash: /root/files.list: Permission denied $ sudo ls -l /root | sudo tee /root/files.list >/dev/null $ sudo ls -l /root/files.list -rw-r--r-- 1 root root 94 Oct 18 09:31 /root/files.list
Do you want to tee the output of a command to a file, but see it in your terminal too, without buffering? The stdbuf command can do this for you:
$ sudo stdbuf --output=L tcpdump -i any -tttt -n 'udp port 5353' | tee -a tcpdump-mdns
tcpdump: data link type LINUX_SLL2
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on any, link-type LINUX_SLL2 (Linux cooked v2), snapshot length 262144 bytes
2023-06-15 11:55:16.637670 eth0 M IP 10.0.0.23.5353 > 224.0.0.251.5353: 0 A (QM)? winnebago.local. (28)
2023-06-15 11:55:16.744660 eth0 M IP 10.0.0.42.5353 > 224.0.0.251.5353: 0*- [0q] 1/0/0 (Cache flush) A 10.0.0.42 (38)
...
$ apt-file find guestmount guestmount: /usr/bin/guestmount guestmount: /usr/share/bash-completion/completions/guestmount guestmount: /usr/share/doc/guestmount/changelog.Debian.gz guestmount: /usr/share/doc/guestmount/copyright guestmount: /usr/share/man/ja/man1/guestmount.1.gz guestmount: /usr/share/man/man1/guestmount.1.gz guestmount: /usr/share/man/uk/man1/guestmount.1.gz
Are you writing a script and some command doesn’t accept hostnames and you don’t want to inline the IP address? dig +short is your friend!
$ dig +short gbenson.net 69.163.152.201
$ apt policy wget
wget:
Installed: 1.21.2-2ubuntu1
Candidate: 1.21.2-2ubuntu1
Version table:
*** 1.21.2-2ubuntu1 500
500 http://gb.archive.ubuntu.com/ubuntu jammy/main amd64 Packages
100 /var/lib/dpkg/status
By the way, if you’ve never used Python’s debugger, it really is as simple as adding a call to the built-in function breakpoint() at the point you want it to stop.
I discovered a new sed trick today:
sed -i~
“I” stands for “in place”. It edits the files in place! And makes a backup if you want!
What’s in my container?
$ podman ps --ns CONTAINER ID NAMES PID CGROUPNS IPC MNT NET PIDNS USERNS UTS fe11359293e8 eloquent_austin 11090 4026532623 4026532621 4026532421 4026532624 4026531837 4026532622
$ sudo ls -l /proc/11090/root/
total 22628
lrwxrwxrwx. 1 root root 7 Jul 25 2019 bin -> usr/bin
dr-xr-xr-x. 2 root root 6 Jul 25 2019 boot
drwxr-xr-x. 5 root root 360 Jan 24 12:03 dev
drwxr-xr-x. 1 root root 183 Jan 23 16:43 etc
...
Thank you.
[28 Jan@1135UTC] UPDATE—Actually, this doesn’t seem to work with newer systems, sorry!