Commands by unixmonkey10186 (1)

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Enable ** to expand files recursively (>=bash-4.0)
Since bash 4.0, you can use ** to recursively expand to all files in the current directory. This behaviour is disabled by default, this command enables it (you'd best put it in your .profile). See the sample output for clarification. In my opinion this is much better than creating hacks with find and xargs when you want to pass files to an application.

Run a command for blocks of output of another command
The given example collects output of the tail command: Whenever a line is emitted, further lines are collected, until no more output comes for one second. This group of lines is then sent as notification to the user. You can test the example with $ logger "First group"; sleep 1; logger "Second"; logger "group"

See multiple progress bars at once for multiple pipes with pv
In this example we convert a .tar.bz2 file to a .tar.gz file. If you don't have Pipe Viewer, you'll have to download it via apt-get install pv, etc.

A simple X11 tea timer
wrapping the snippet in $( )& puts the whole thing in the background so you don't tie up your login session.

Check a nfs mountpoint and force a remount if it does not reply after a given timeout.
Based on the execute with timeout command in this site. A more complex script: #!/bin/sh # This script will check the avaliability of a list of NFS mount point, # forcing a remount of those that do not respond in 5 seconds. # # It basically does this: # NFSPATH=/mountpoint TIMEOUT=5; perl -e "alarm $TIMEOUT; exec @ARGV" "test -d $NFSPATH" || (umount -fl $NFSPATH; mount $NFSPATH) # TIMEOUT=5 SCRIPT_NAME=$(basename $0) for i in $@; do echo "Checking $i..." if ! perl -e "alarm $TIMEOUT; exec @ARGV" "test -d $i" > /dev/null 2>&1; then echo "$SCRIPT_NAME: $i is failing with retcode $?."1>&2 echo "$SCRIPT_NAME: Submmiting umount -fl $i" 1>&2 umount -fl $i; echo "$SCRIPT_NAME: Submmiting mount $i" 1>&2 mount $i; fi done

check open ports without netstat or lsof

Show directories in the PATH, one per line
Shorter version.

A signal trap that logs when your script was killed and what other processes were running at that time
trap is the bash builtin that allows you to execute commands when the current script receives a particular signal. Uses $0 for the script name, $$ for the script PID, tee to output to STDOUT as well as a log file and ps to log other running processes.

Pipe stdout and stderr, etc., to separate commands
You can use [n]> combined with >(cmd) to attach the various output file descriptors to be the input of different commands.

Stop Flash from tracking everything you do.
Brute force way to block all LSO cookies on a Linux system with the non-free Flash browser plugin. Works just fine for my needs. Enjoy.


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