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create random string from /dev/urandom (or another length)

Pulls email password out of Plesk database for given email address.
This simply pulls the password out of the database for the given mail name for ease of use in testing emails that you would not normally have access to.

exclude a column with cut
Show all columns except 5th. This might help you save some typing if you are trying to exclude some columns from the output.

Combine two mp3's or more into 1 long mp3
This just combines multiple mp3's into one mp3 file. Basically it is a easy join for mp3's

Create a backup copy of a MySQL database on the same host
This should probably only be used for testing in a dev environment as it's not terribly efficient, but if you're doing something that might trash a DB and you still want the old data available, this works like a charm.

take execution time of several commands
The last ; is important. example: time { rm -rf /folder/bar && mkdir -p /folder/bar ; echo "done" ; } command is a bash builtin

Loops over files, runs a command, dumps output to a file
In this case I'm selecting all php files in a dir, then echoing the filename and piping it to ~/temp/errors.txt. Then I'm running my alias for PHPCS (WordPress flags in my alias), then piping the PHPCS output to grep and looking for GET. Then I'm piping that output to the same file as above. This gets a list of files and under each file the GET security errors for that file. Extrapolate this to run any command on any list of files and pipe the output to a file. Remove the >> ~/temp/errors.txt to get output to the screen rather than to a file.

split a file by a specific number of lines
Splits the file "my_file" every 500 lines. Will create files called xx01 xx02 and so on. You can change the prefix by using the -f option. Comes in handy for splitting logfiles for example. I am using it for feeding a logfile parser with smaller files instead of one big file (due to performance reasons)

find and delete empty directories recursively
this will show the names of the deleted directories, and will delete directories that only no files, only empty directories.

List known debian vulnerabilities on your system -- many of which may not yet be patched.
You can search for CVEs at https://security-tracker.debian.org/tracker/ or use --report to get full links. This can be added to cron, but unless you're going to do manual patches, you'd just be torturing yourself.


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