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Resume a detached screen session, resizing to fit the current terminal
By default, screen tries to restore its old window sizes when attaching to resizable terminals. This command is the command-line equivalent to typing ^A F to fit an open screen session to the window.

list all file-types (case-insensitive extensions) including subdirectories

Scan a gz file for non-printable characters and display each line number and line that contains them.
Scans the file once to build a list of line numbers that contain non-printable characters Scans the file again, passing those line numbers to sed as two commands to print the line number and the line itself. Also passes the output through a tr to replace the characters with a ?

Quickly analyse an Apache error log
This searches the Apache error_log for each of the 5 most significant Apache error levels, if any are found the date is then cut from the output in order to sort then print the most common occurrence of each error.

Blacklist usb storage
Some times you may ban usb to protect thefting of your personal data. Blacklist the usb_storage module by adding blacklist usb_storage to /etc/modprobe.d/blacklist.conf. To load the module manually, $sudo modprobe usb_storage.

Quick notepad
Quick write some notes to a file with cat. Ctrl+C when you have finish.

delete duplicate lines from a file and keep the order of the other lines
i wanted to delete all duplicate lines from .bash_history and keep the order of the other lines. the command cat's the file and adds line numbers, then sorts by the second column. afterwards uniq omits repeated lines, but skips the first field (the line number). then it sorts by the line numbers and at the end cuts the numbers off.

Cleanup a (source) text file, removing trailing spaces/tabs and multiple consecutive blank lines
I used this command (in addition to a code formatting tool) to "cleanup" a bunch of PHP files

Display top 5 processes consuming CPU

Automatic ssh Session Logger
A wrapper around ssh to automatically provide logging and session handling. This function runs ssh, which runs screen, which runs script. . The logs and the screen session are stored on the server. This means you can leave a session running and re-attach to it later, or from another machine. . . Requirements: * Log sessions on a remote server * Transparent - nothing extra to type * No installation - nothing to copy to the server beforehand . Features: * Function wrapper delegating to ssh - so nothing to remember - uses .ssh/config as expected - passes your command line option to ssh * Self-contained: no scripts to install on the server * Uses screen(1), so is: - detachable - re-attachable - shareable * Records session using script(1) * Configurable log file location, which may contain variables or whitespace L="$HOME" # local variable L="\$HOME" # server variable L="some space" . Limitations: * Log dir/file may not contain '~' (which would require eval on the server) . . The sessions are named by the local user connecting to the server. Therefore if you detach and re-run the same command you will reconnect to your original session. If you want to connect/share another's session simply run: $ USER=bob ssh root@server . The command above is stripped down to an absolute minimum. A fully expanded and annotated version is available as a Gist (git pastebin): https://gist.github.com/flatcap/3c42326abeb1197ee714 . If you want to add timing info to script, change the command to: $ ssh(){ L="\$HOME/logs/$(date +%F_%H:%M)-$USER";/usr/bin/ssh -t "$@" "mkdir -p \"${L%/*}\";screen -xRRS $USER script --timing=\"$L-timing\" -f \"$L\"";}


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