Get your external IP address
curl ifconfig.me
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curl ifconfig.me/ip -> IP Adress
curl ifconfig.me/host -> Remote Host
curl ifconfig.me/ua ->User Agent
curl ifconfig.me/port -> Port
intercept stdout/stderr of another process
strace -ff -e trace=write -e write=1,2 -p SOME_PID
Delete all files in a folder that don’t match a certain file extension
Deletes all files in a folder that are NOT *.foo, *.bar or *.baz files. Edit the pattern inside the brackets as you like.
rm !(*.foo|*.bar|*.baz)
