Commands using head (314)

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Block known dirty hosts from reaching your machine
Blacklisted is a compiled list of all known dirty hosts (botnets, spammers, bruteforcers, etc.) which is updated on an hourly basis. This command will get the list and create the rules for you, if you want them automatically blocked, append |sh to the end of the command line. It's a more practical solution to block all and allow in specifics however, there are many who don't or can't do this which is where this script will come in handy. For those using ipfw, a quick fix would be {print "add deny ip from "$1" to any}. Posted in the sample output are the top two entries. Be advised the blacklisted file itself filters out RFC1918 addresses (10.x.x.x, 172.16-31.x.x, 192.168.x.x) however, it is advisable you check/parse the list before you implement the rules

Cropping a video file in ffmpeg

Have your sound card call out elapsed time.
Useful contexts : You are doing yoga or some other physical training in which you are holding a position. Or you practice the pomodoro productivity technique. Or your girlfriend said "We're leaving in 40 minutes". Design details: sleep executes before espeak to give you a 5 seconds head start. espeak is run in the background so it doesn't mess up the timing.

change microdvd subtitles framerate
this command example converts to 25 fps subtitles that were originally created for 24 fps movie

diff current vi buffer edits against original file

count and number lines of output, useful for counting number of matches
Write each FILE to standard output, with line numbers added. With no FILE, or when FILE is -, read standard input.

Show all programs on UDP and TCP ports with timer information
-p PID and name of the program -u on a UDP port. -t also TCP ports -o networking timer -n numeric IP addresses (don't resolve them) -a all sockets

Rename files in batch

Check your unread Gmail from the command line
Just an alternative with more advanced formating for readability purpose. It now uses colors (too much for me but it's a kind of proof-of-concept), and adjust columns.

Use /dev/full to test language I/O-failsafety
The Linux /dev/full file simulates a "disk full" condition, and can be used to verify how a program handles this situation. In particular, several programming language implementations do not print error diagnostics (nor exit with error status) when I/O errors like this occur, unless the programmer has taken additional steps. That is, simple code in these languages does not fail safely. In addition to Perl, C, C++, Tcl, and Lua (for some functions) also appear not to fail safely.


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