Bash-Hacks One useful bash one-liner every weekday, explained flag by flag. https://bash-hacks.com/ 2026-09-16T00:00:00.000Z See exactly what rsync will change before it changes anything https://bash-hacks.com/2026/09/16/023-see-what-rsync-will-do-before-it-runs/ 2026-09-16T00:00:00.000Z rsync -avni --delete site/ backup/ Total a column grouped by another one in a single pass https://bash-hacks.com/2026/09/15/022-total-a-column-grouped-by-another/ 2026-09-15T00:00:00.000Z awk '{n[$7]++; bytes[$7]+=$10} END {for (u in n) printf "%12.0f %6d %s\n", bytes[u], n[u], u}' access.log | sort -rn | head Find the process that is quietly eating your memory https://bash-hacks.com/2026/09/14/021-find-the-process-eating-your-memory/ 2026-09-14T00:00:00.000Z ps -eo pid,ppid,rss,etimes,pcpu,comm --sort=-rss | head -11 Search a project without walking into node_modules https://bash-hacks.com/2026/09/08/018-search-a-project-without-walking-into-node-modules/ 2026-09-08T00:00:00.000Z find . \( -name node_modules -o -name .git \) -prune -o -type f -name '*.ts' -print Find out which part of an HTTP request is actually slow https://bash-hacks.com/2026/09/07/017-find-out-which-part-of-a-request-is-slow/ 2026-09-07T00:00:00.000Z curl -sS -o /dev/null -w "dns %{time_namelookup}\ntcp %{time_connect}\ntls %{time_appconnect}\nttfb %{time_starttransfer}\ntotal %{time_total}\n" https://www.debian.org Bring back the commits you lost to a bad reset https://bash-hacks.com/2026/09/04/016-bring-back-commits-lost-to-a-bad-reset/ 2026-09-04T00:00:00.000Z git reflog show --date=relative HEAD Compare the output of two commands without writing a temp file https://bash-hacks.com/2026/09/03/015-compare-the-output-of-two-commands/ 2026-09-03T00:00:00.000Z diff <(sort packages-web01.txt) <(sort packages-web02.txt) Turn a Unix timestamp into a readable date in any timezone https://bash-hacks.com/2026/09/02/014-read-a-unix-timestamp-in-any-timezone/ 2026-09-02T00:00:00.000Z TZ=America/New_York date -d @1788373391 +'%F %T %Z' Reuse SSH connections instead of authenticating every time https://bash-hacks.com/2026/09/01/013-reuse-ssh-connections-with-controlmaster/ 2026-09-01T00:00:00.000Z ssh -o ControlMaster=auto -o ControlPath=~/.ssh/sockets/%r@%h-%p -o ControlPersist=600 devbox See what is inside a tarball without extracting it https://bash-hacks.com/2026/08/31/012-see-whats-inside-a-tarball-without-extracting/ 2026-08-31T00:00:00.000Z tar -tzvf archive.tar.gz Find out what a command actually is before you run it https://bash-hacks.com/2026/08/28/011-find-out-what-a-command-actually-is/ 2026-08-28T00:00:00.000Z type -a grep Check how much disk space is left on every mounted filesystem https://bash-hacks.com/2026/08/27/010-check-how-much-disk-space-is-left/ 2026-08-27T00:00:00.000Z df -h Search your Git history for a deleted function or string https://bash-hacks.com/2026/08/26/009-search-git-history-for-deleted-code/ 2026-08-26T00:00:00.000Z git log -S"handleAuth" --oneline --all Check where a domain name actually points https://bash-hacks.com/2026/08/25/008-check-where-a-domain-points/ 2026-08-25T00:00:00.000Z dig +short example.com Sort a CSV by any column without opening a spreadsheet https://bash-hacks.com/2026/08/24/007-sort-csv-by-column/ 2026-08-24T00:00:00.000Z sort -t, -k3 -nr sales.csv | head -20 Find out what is actually eating your disk https://bash-hacks.com/2026/08/21/006-find-what-is-eating-your-disk/ 2026-08-21T00:00:00.000Z du -h -d1 . | sort -hr | head -10 Find out which process is sitting on port 8080 https://bash-hacks.com/2026/08/20/005-find-process-on-port-8080/ 2026-08-20T00:00:00.000Z lsof -nP -iTCP:8080 -sTCP:LISTEN