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Unix commandline history substitution like ^foo^bar BUT for multiple replacements
#1 You invoked a command chain. #2 You globaly replace the scriptnames and execute them direct #3 The new executed command chain [# ^foo^bar] would only replace the firts match [foo] with [bar].

clean up syntax and de-obfuscate perl script
the command show can be run in vim, here is the same thing on the command line $ cat script.pl | perl -MO=Deparse | perltidy

resize all JPG images in folder and create new images (w/o overwriting)
Convert all jpegs in the current directory into ~1024*768 pixels and ~ 150 KBytes jpegs

Find processes stuck in dreaded "D" state aka IO Wait
Lots of fun to run on nfs clients when the server or network connection is having issues

Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

Assign top-level JSON entries to shell variables
A recursive version might be useful too. /dev/tty is used to show which shell variables just got defined.

Create a tar archive using xz compression
compress directory archive with xz compression, if tar doesn't have the -J option (OSX tar doesn't have -J)

move messages directly from one IMAP inbox to another
This one-liner was useful in helping someone I know to get off of MS Exchange. `mailutil` proved to be a much better alternative than `fetchmail` or `getmail` in this case. It quickly moved all mails to the destination server (a simple Dovecot/Maildir setup), with no need to convert back and forth between mbox/maildir on the user's own system.

Generate a random password 30 characters long
According to the gpg(1) manual: --gen-random 0|1|2 count Emit count random bytes of the given quality level 0, 1 or 2. If count is not given or zero, an endless sequence of random bytes will be emitted. If used with --armor the output will be base64 encoded. PLEASE, don't use this command unless you know what you are doing; it may remove precious entropy from the system! If your entropy pool is critical for various operations on your system, then using this command is not recommended to generate a secure password. With that said, regenerating entropy is as simple as: $ du -s / This is a quick way to generate a strong, base64 encoded, secure password of arbitrary length, using your entropy pool (example above shows a 30-character long password).

Export MySQL tables that begin with a string


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