Commands by vincentp (4)

  • This command gives you the number of lines of every file in the folder and its subfolders matching the search options specified in the find command. It also gives the total amount of lines of these files. The combination of print0 and files0-from options makes the whole command simple and efficient. Show Sample Output


    2
    find . -name "*.sql" -print0 | wc -l --files0-from=-
    vincentp · 2009-06-22 17:45:03 2
  • Finds all corrupted jpeg files in current directory and its subdirectories. Displays the error or warning found. The jpeginfo is part of the jpeginfo package in debian. Should you wish to only get corrupted filenames, use cut to extract them : find ./ -name *jpg -exec jpeginfo -c {} \; | grep -E "WARNING|ERROR" | cut -d " " -f 1 Show Sample Output


    13
    find . -name "*jpg" -exec jpeginfo -c {} \; | grep -E "WARNING|ERROR"
    vincentp · 2009-06-03 22:08:48 3
  • wraps text lines at the specified width (90 here). -s option is to force to wrap on blank characters -b count bytes instead of columns


    12
    fold -s -w 90 file.txt
    vincentp · 2009-05-11 23:00:25 1
  • Find all corrupted jpeg in the current directory, find a file with the same name in a source directory hierarchy and copy it over the corrupted jpeg file. Convenient to run on a large bunch of jpeg files copied from an unsure medium. Needs the jpeginfo tool, found in the jpeginfo package (on debian at least).


    0
    for i in *jpg; do jpeginfo -c $i | grep -E "WARNING|ERROR" | cut -d " " -f 1 | xargs -I '{}' find /mnt/sourcerep -name {} -type f -print0 | xargs -0 -I '{}' cp -f {} ./ ; done
    vincentp · 2009-05-07 00:30:36 0

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Change newline to space in a file just using echo
Changing newline to spaces using just echo

Mount a partition from within a complete disk dump
Instead of calculating the offset and providing an offset option to mount, let lomount do the job for you by just providing the partition number you would like to loop mount.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

kde4 lock screen command
If you wish to launch the kde4 screen saver without the password prompt to exit, use this command: $ qdbus org.freedesktop.ScreenSaver /ScreenSaver org.freedesktop.ScreenSaver.SetActive True Also can be done with: $ /usr/lib/kde4/libexec/kscreenlocker --forcelock

quick copy
Utilizes shell expansion of {} to give the original filename and a new filename as arguments to `cp`. Can easily be extended to make multiple copies.

Backup with versioning
Apart from an exact copy of your recent contents, also keep all earlier versions of files and folders that were modified or deleted. Inspired by the excellent EVACopy http://evacopy.sourceforge.net

Delete empty, 24-hours-old directories recursively, without consider hidden directories

Get current stable kernel version string from kernel.org
depends on "jq" This is more reliable in my opinion.

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"

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.


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