Commands by fraktil (4)

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Convert control codes to visible Unicode Control Pictures
Converts control codes and spaces (ASCII code ≤ 32) to visible Unicode Control Pictures, U+2400 ? U+2420. Skips \n characters, which is probably a good thing.

MySQL dump restore with progress bar and ETA
Display a progress bar while restoring a MySQL dump.

read a file line by line and perform some operation on each line
see sample output

Get all available packages on Ubuntu (or any distro that uses apt)

List open sockets protocol/address/port/state/PID/program name

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

Find recursively, from current directory down, files and directories whose names contain single or multiple whitespaces and replace each such occurrence with a single underscore.
Note the g for global in the perl expression; without it, only the first occurrence in the name would be replaced.

add the result of a command into vi
':r!ls -l' results in listing the files in the current directory and paste it into vi

Emptying a text file in one shot
Within vi allow to empty a text file in one shot

Put uppercase letters in curly brackets in a BibTeX database
It is often recommended to enclose capital letters in a BibTeX file in braces, so the letters will not be transformed to lower case, when imported from LaTeX. This is an attempt to apply this rule to a BibTeX database file. DO NOT USE sed '...' input.bib > input.bib as it will empty the file! How it works: $ /^\s*[^@%]/ Apply the search-and-replace rule to lines that start (^) with zero or more white spaces (\s*), followed by any character ([...]) that is *NOT* a "@" or a "%" (^@%). $ s===g Search (s) for some stuff and replace by other stuff. Do that globally (g) for all matches in each processed line. $ \([A-Z][A-Z]*\)\([^}A-Z]\|},$\) Matches at least one uppercase letter ([A-Z][A-Z]*) followed by a character that is EITHER not "}" and not a capital letter ([^}A-Z]) OR (|) it actually IS a "}", which is followed by "," at the end of the line ($). Putting regular expressions in escaped parentheses (\( and \), respectively) allows to dereference the matched string later. $ {\1}\2 Replace the matched string by "{", followed by part 1 of the matched string (\1), followed by "}", followed by the second part of the matched string (\2). I tried this with GNU sed, only, version 4.2.1.

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