Commands by aliboy (2)

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Find the package that installed a command

Console clock
Shows a simple clock in the console -t param removes the watch header Ctrl-c to exit

clean up memory of unnecessary things (Kernerl 2.6.16 or newer)
run sync first to flush useful things out to disk!!! To free pagecache: echo 1 > /proc/sys/vm/drop_caches To free dentries and inodes: echo 2 > /proc/sys/vm/drop_caches To free pagecache, dentries and inodes: echo 3 > /proc/sys/vm/drop_caches

sed /pat/!d without using sed (no RE; limited to shell patterns aka globbing)
POSIX requires this "string truncating" functionality. might as well use it, at least for very small tasks where invoking sed and using RE is overkill.

diff output of two commands
This only works in bash

Using column to format a directory listing
Using column to format a directory listing

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.

Rot13 using the tr command
rot13 maps a..mn..z (A..MN..Z) to n..za..m (n..za..m) and so does this alias.

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"

Setting global redirection of STDERR to STDOUT in a script
You have a script where =ALL= STDERR should be redirected to STDIN and you don't want to add "2>&1" at the end of each command... E.G.: $ ls -al /foo/bar 2>&1 Than just add this piece of code at the beginning of your script! I hope this can help someone. :)


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