Commands by roliver (1)

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commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

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Copy files from multiple directories into one directory

Big Countdown Clock with hours, minutes and seconds
Figlet is easy to find for download on the internet, and works for any text. Quite cool.

grep for minus (-) sign
Use flag "--" to stop switch parsing

Batch Convert SVG to PNG (in parallel)
Convert some SVG files into PNG using ImageMagick's convert command. Run the conversions in parallel to save time. This is safer than robinro's forkbomb approach :-) xargs runs four processes at a time -P4

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Download 10 random wallpapers from images.google.com

List all active access_logs for currently running Apache or Lighttpd process
Ever logged into a *nix box and needed to know which webserver is running and where all the current access_log files are? Run this one liner to find out. Works for Apache or Lighttpd as long as CustomLog name is somewhat standard. HINT: works great as input into for loop, like this: $ for i in `lsof -p $(netstat -ltpn|awk '$4 ~ /:80$/ {print substr($7,1,index($7,"/")-1)}')| awk '$9 ~ /access.log$/ {print $9| "sort -u"}'` ; do echo $i; done Very useful for triage on unfamiliar servers!

Alternative size (human readable) of files and directories (biggest last)
using mb it's still readable;) a symbol variation $ du -ms {,.[^.]}* | sort -nk1

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Monitor a file with tail with timestamps added
This is useful when watching a log file that does not contain timestamps itself. If the file already has content when starting the command, the first lines will have the "wrong" timestamp when the command was started and not when the lines were originally written.


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