General
Check Network Utilization
sudo iftop -B
Process Substitution
Creating a named pipe is done in fish with the psub command as follows:
diff (sort a.txt | psub) (sort b.txt | psub)
References: man psub
Extract and Pretty Print Stack Trace from Logback Logs
cat tmp | jq ".stack_trace" | xargs printf
Less
Tips and tricks with less
Display ANSI color codes
less -R
Display Line Numbers
less -N
All these less commands can be passed in as args, or when already in less. Also, some of the search and movement syntax of vim works in less as well.
Tcpdump
Direct Usage
To make the output legible, as well as manageable, make sure to
- specify the port you care about
- use the -XX and -i flags to get ascii output next to the binary
sudo tcpdump -XX -i eth0 port 44380 > /tmp/dump
Pretty Print PCAP file
If you have an existing PCAP file (for example, from wireshark), you can run it through tcpdump to pretty print the contents as follows:
tcpdump -qns 0 -X -r file.pcap
Find
List files with specific extension and perform command on them
# In this case, list video files and for each one, extract metadata
find . -type f \( -iname \*.mkv -o -iname \*.mp4 -o -iname \*.avi \) -print0 | while IFS= read -r -d '' file; do
ffprobe -v quiet -print_format json -show_format -show_streams $file;
done > ~/video_metadata.json