Commands by cognosco41 (1)

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Quickly generate an MD5 hash for a text string using OpenSSL
Here Strings / A variant of here documents, the format is:

Upgrade all perl modules via CPAN

Press ctrl+r in a bash shell and type a few letters of a previous command
In the sample output, I pressed ctrl+r and typed the letters las. I can't imagine how much typing this has saved me.

Read aloud a text file in Ubuntu (and other Unixes with espeak installed

Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

MSDOS command to check existance of command and exit batch if failed
This is a command to be used inside of MS-DOS batch files to check existence of commands as preconditions before actual batch processing can be started. If the command is found, batch script continues execution. If not, a message is printed on screen, script then waits for user pressing a key and exits. An error message of the command itself is suppressed for clarity purpose.

Get all IPs via ifconfig
works on Linux and Solaris. I think it will work on nearly all *nix-es

Show drive names next to their full serial number (and disk info)
As of this writing, this requires a fairly recent version of util-linux, but is much simpler than the previous alternatives. Basically, lsblk gives a nice, human readable interface to all the blkid stuff. (Of course, I wouldn't recommend this if you're going to be parsing the output.) This command takes all the fun out of the previous nifty pipelines, but I felt I ought to at least mention it as an alternative since it is the most practical.

Insert the last argument of the previous command

dmesg with colored human-readable dates
Use sed to color the output of a human-readable dmesg output


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