Commands by bendavis78 (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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Extract JPEG images from a PDF document
This will extract all DCT format images from foo.pdf and save them in JPEG format (option -j) to bar-000.jpg, bar-001.jpg, bar-002.jpg, etc. Inspired by

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"

List all files opened by a particular command
List all file opened by a particular command based on it's command name.

Watch and cat the last file to enter a directory
Great for watching things like Maildir's or any other queue directory.

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" }

Indent a one-liner.
I often write a one-liner which I want to use later in a script.

Sort netflow packet capture
Sort netflow packet capture by unique connections excluding source port.

Colour part of your prompt red to indicate an error
If the return code from the last command was greater than zero, colour part of your prompt red. The commands give a prompt like this: [user current_directory]$ After an error, the "[user" part is automatically coloured red. Tested using bash on xterm and terminal. Place in your .bashrc or .bash_profile.

check open ports without netstat or lsof

Batch file name renaming (copying or moving) w/ glob matching.

Stay in the loop…

Follow the Tweets.

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