Commands by lysergication (2)

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Shell recorder with replay
If you provide the option -t to the script command and redirect stderr into a file, the timing information on what is going on on the terminal, is also stored. You can replay the session via the scriptreplay command, where you can also provide a speedup factor (see the man page for details). Great for demonstration purposes ...

Runs previous command replacing foo by bar every time that foo appears
Very useful for rerunning a long command changing some arguments globally. As opposed to ^foo^bar, which only replaces the first occurrence of foo, this one changes every occurrence.

Force logout after 24 hours idle
Shell timeout variables (TMOUT) can be very liberal about what is classified as 'activity', like having an editor open. This command string will terminate the login shell for an user with more than a day's idle time.

Generate random valid mac addresses
Python Alternative

Validate and pretty-print JSON expressions.
You can use a site like http://www.jsonlint.com/ or use the command line to validate your long and complex json data. This is part of the simplejson package for python http://undefined.org/python/#simplejson. Wrong json expression example: $ echo '{ 1.2:3.4}' | python -m simplejson.tool Expecting property name: line 1 column 2 (char 2)

Set the hardware date and time based on the system date

Move all files between to date
In a folder with many files and folders, you want to move all files where the date is >= the file olderFilesNameToMove and

list block devices
Shows all block devices in a tree with descruptions of what they are.

Show UDID of iPhone
Display the serial of the iPhone (aka UDID).

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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