Commands by aajjk (1)

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Find processes utilizing high memory in human readable format
Finding high memory usage report in human readable format.

How to backup hard disk timely?
Creates files in $DATE and hardlinks existing files to $PREVDATE. Thus full backup in each directory. Only drawback is changed modification time. Recommend a wrapper script to determine $DATE and $PREVDATE. Works like a charm. (Dirvish handrolled)

Rename files in batch

use vi key bindings at the command line

bash script to zip a folder while ignoring git files and copying it to dropbox
Better tool for exporting git's repository is Git itself!

Run a ext4 file system check and badblocks scan with progress info
Nothing fancy, just a regular filesystem scan that calls the badblocks program and shows some progress info. The used options are: -c ? check for bad sectors with badblocks program -D ? optimize directories if possible -f ? force check, even if filesystem seems clean -t ? print timing stats (use -tt for more) -y ? assume answer ?yes? to all questions -C 0 ? print progress info to stdout /dev/sdxx ? the partition to check, (e.g. /dev/sda1 for first partition on first hard disk) NOTE: Never run fsck on a mounted partition!

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

grep (or anything else) many files with multiprocessor power
xargs -P N spawns up to N worker processes. -n 40 means each grep command gets up to 40 file names each on the command line.

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

setup a tunnel from destination machine port 80 to localhost 2001, via a second (hub) machine.
this is handy when the hubmachine is the only machine that can connect to the destination machine (allowed on ip by firewall) and you want to access it from your laptop.


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