Commands by richard (5)

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Erase CD RW

Copy structure
Copies a dir structure without the files in it.

Read PDFs in the command line
Turns a PDF into HTML (without images) and prints it to the standard out which is picked up and interpreted by w3m.

Download a new release of a program that you already have very quickly
Zsync is an implementation of rsync over HTTP that allows updating of files from a remote Web server without requiring a full download. For example, if you already have a Debian alpha, beta or RC copy downloaded, zsync can just download the updated bits of the new release of the file from the server. This requires the distributor of the file to have created a zsync build control file (using zsyncmake).

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" }

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

locate a filename, make sure it exists and display it with full details
use the locate command to find files on the system and verify they exist (-e) then display each one in full details.

What is the use of this switch ?
e.g. $ manswitch grep -o This will take you to the relevant part of the man page, so you can see the description of the switch underneath.

Rename many files in directories and subdirectories
This is probably overkill, but I have some issues when the directories have spaces in their names. The $ find . -type d -print0 | while read -d $'\0' dir; do xxx; done loops over all the subdirectories in this place, ignoring the white spaces (to some extend). $ cd "$dir"; echo " process $dir"; cd -; goes to the directory and back. It also prints some info to check the progress. $ find . -maxdepth 1 -name "*.ogg.mp3" -exec rename 's/.ogg.mp3/.mp3/' {} \; renames the file within the current directory. The whole should work with directories and file names that include white spaces.

find and reduce 8x parallel the size of JPG images without loosing quality via jpegoptim


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