Commands by brockangelo (3)

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Upgrading packages. Pacman can update all packages on the system with just one command. This could take quite a while depending on how up-to-date the system is. This command can synchronize the repository databases and update the system's packages.
Warning: Instead of immediately updating as soon as updates are available, users must recognize that due to the nature of Arch's rolling release approach, an update may have unforeseen consequences. This means that it is not wise to update if, for example, one is about to deliver an important presentation. Rather, update during free time and be prepared to deal with any problems that may arise. Pacman is a powerful package management tool, but it does not attempt to handle all corner cases. Read The Arch Way if this causes confusion. Users must be vigilant and take responsibility for maintaining their own system. When performing a system update, it is essential that users read all information output by pacman and use common sense. If a user-modified configuration file needs to be upgraded for a new version of a package, a .pacnew file will be created to avoid overwriting settings modified by the user. Pacman will prompt the user to merge them. These files require manual intervention from the user and it is good practice to handle them right after every package upgrade or removal. See Pacnew and Pacsave Files for more info. Tip: Remember that pacman's output is logged in /var/log/pacman.log.

Print the IPv4 address of a given interface

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.

Show drive names next to their full serial number (and disk info)
Scrap everything and use `gawk` to do all the magic, since it's like the future or something. $ gawk 'match($11, /[a-z]{3}$/) && match($9, /^ata-/) { gsub("../", ""); print $11,"\t",$9 }' Yank out only ata- lines that have a drive letter (ignore lines with partitions). Then strip ../../ and print the output. Yay awk. Be sure to see the alternatives as my initial command is listed there. This one is a revision of the original.

Keep track of diff progress
You're running a program that reads LOTS of files and takes a long time. But it doesn't tell you about its progress. First, run a command in the background, e.g. $ find /usr/share/doc -type f -exec cat {} + > output_file.txt Then run the watch command. "watch -d" highlights the changes as they happen In bash: $! is the process id (pid) of the last command run in the background. You can change this to $(pidof my_command) to watch something in particular.

list files recursively by size

Quick searching with less
This command enables the user to append a search pattern on the command line when using less as the PAGER. This is especially convenient (as the example shows) in compressed files and when searching man pages (substituting the zcat command with man, however).

1+2-3+4-5+6-7 Series

Print the 16 most recent RPM packages installed in newest to oldest order

Extract JPEG images from a PDF document
This will extract all DCT format images from foo.pdf and save them in JPEG format (option -j) to bar-000.jpg, bar-001.jpg, bar-002.jpg, etc. Inspired by http://stefaanlippens.net/extract-images-from-pdf-documents


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