TIL - Today I Learned
Things I learned from colleagues, the internet or just out of curiosity.
tail -f <logfile> | grep --line-buffered: filter logfile continuously while debugging a service or some ongoing process&<term>inless: show only lines matching filter in less pagerctrl+x ctrl+einbash: opens default editor (specified with$EDITORor$VISUAL) for specifying a prompt, will get executed on save+close (src, look foredit-and-execute-command).ctrl+rinbash: fuzzy search in bash history, press again for cycling throughctrl+xandctrl+aon an action while interactive rebase: cycle through the rebase actions when interactively rebasing within an editor (git rebase -i)yes | dd oflag=/mnt/data iflag=fullblock oflag=direct bs=16M count=$((1024*1024/16)) status=progress: generate 1TB of non-random test data with storage backend speed, avoid buffering where possiblego doc --all strings: local documentation of the gostringspackagedu --summarize -h .: show summarized usage of a folder human friendlyag -G <filename-pattern> <search-pattern>: only search in files matching the filename pattern with the silver-searcherag(?:<pattern>): regex matches pattern but without generating a capture-groupdpkg -S <file>: query package providing given file on debian-based systemsdpkg -L <package>: list all files of an installed dpkg packageecho lol|/usr/bin/cat /dev/stdin: use/dev/stdinas filename when the stdout from previous command schould be used. Useful for commands not supporting stdin as input source.vim <url>: open vim, download and show content of the given urltcpdump -i <interface> -pvn port 67 and port 68: see dhcp requests and responses for<interface>- Adding a space before a bash command prevents it from being written to the history.
date +"%s": show current time as unix timestampdate -d @<unix-timestamp>: convert unix timestamp into a human readable onectrl+zandfg: suspend running applications viactrl+zto get to the original shell and get back to the application viafg