Commands by pornel (2)

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Summarize size of all files of given type in all subdirectories (in bytes)
This deals nicely with filenames containing special characters and can deal with more files than can fit on a commandline. It also avoids spawning du.

Backup a file with a date-time stamp
$ buf myfile.txt This is useful when you are making small but frequent changes to a file. It keeps things organised and clear for another administrator to see what changed and at what time. An overview of changes can be deduced using a simple: $ ls -ltr

Search for a string inside all files in the current directory
This is how I typically grep. -R recurse into subdirectories, -n show line numbers of matches, -i ignore case, -s suppress "doesn't exist" and "can't read" messages, -I ignore binary files (technically, process them as having no matches, important for showing inverted results with -v) I have grep aliased to "grep --color=auto" as well, but that's a matter of formatting not function.

cd to (or operate on) a file across parallel directories
This is useful for quickly jumping around branches in a file system, or operating on a parellel file. This is tested in bash. cd to (substitute in PWD, a for b) where PWD is the bash environmental variable for the "working directory"

Save the current directory without leaving it
Save the current directory without having to leave it. When you do decide to leave the current directory, use popd to return to it.

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"

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

Get curenttly playing track in Last.fm radio

Database size
Mysql command to list the disk usage of the database

xargs for builtin bash commands
Similar to xargs -i, but works with builtin bash commands (rather than running "bash -c ..." through xargs)

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