Commands by lysergication (2)

What's this? is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

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count files by type
displays a list of all file extensions in current directory and how many files there are of each type of extension in ascending order (case insensitive)

find all executable files across the entire tree
I can think of using this command after compiling an downloaded source from anywhere as an easy way to find all executable products. We usually issue the $ find command (without arguments) to list the full paths of all directories and sub-directories and files in the entire current tree. Similar command is $ tree -aicfnF

List of directories sorted by number of files they contain.

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" }

Tar - Compress by excluding folders
If you give tar a list of filenames, it will not add the directories, so if you don't care about directory ownership or permissions, you can save some space. Tar will create directories as necessary when extracting. This command is limited by the maximum supported size of the argument list, so if you are trying to tar up the whole OS for instance, you may just get "Argument list too long".

Create new user with home dir and given password
The crypt function takes a password, key, as a string, and a salt character array which is described below, and returns a printable ASCII string which starts with another salt. It is believed that, given the output of the function, the best way to find a key that will produce that output is to guess values of key until the original value of key is found. from

Extract title from HTML files
not the best, uses 4 pipes!

Copy all documents PDF in disk for your home directory
I used this to copy all PDFs recursively to a selected dir

Rename files in batch

list with full path

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