Commands by IndustrialJoe (1)

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Schedule a script or command in x num hours, silently run in the background even if logged out
This is helpful for shell scripts, I use it in my custom php install script to schedule to delete the build files in 3 hours, as the php install script is completely automated and is made to run slow. Does require at, which some environments without crontab still do have. You can add as many commands to the at you want. Here's how I delete them in case the script gets killed. (trapped) atq |awk '{print $1}'|xargs -iJ atrm J &>/dev/null

Use tee + process substitution to split STDOUT to multiple commands
Using process substitution, we can 'trick' tee into sending a command's STDOUT to an arbitrary number of commands. The last command (command4) in this example will get its input from the pipe.

Function that counts recursively number of lines of all files in specified folders

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"

'hpc' in the box - starts a maximum of n compute commands modulo n controlled in parallel
the block of the loop is useful whenever you have huge junks of similar jobs, e.g., convert high res images to thumbnails, and make usage out of all the SMP power on your compute box without flooding the system. note: c is used as counter and the random sleep $ r=`echo $RANDOM%5 |bc`; echo "sleep $r"; sleep $r is just used as a dummy command.

git log with color and path
Cool alias that show a a better Git log

Compare two directory trees.

recursive search and replace old with new string, inside files
xargs deals badly with special characters (such as space, ' and "). To see the problem try this: touch important_file touch 'not important_file' ls not* | xargs rm Parallel https://savannah.nongnu.org/projects/parallel/ does not have this problem.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

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"


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