Commands using tail (292)

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cat large file to clipboard with speed-o-meter
shortest alternative without the speed-o-meter"xclip large.xml" "xclip -o" to get the clipboard content, alternatively [shift key] + insert or middle button of your mouse.

print crontab entries for all the users that actually have a crontab
This is how I list the crontab for all the users on a given system that actually have a crontab. You could wrap it with a function block and place it in your .profile or .bashrc for quick access. There's prolly a simpler way to do this. Discuss.

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" }

Clean pacman cache in arch linux, manjaro linux
If not success clean cache and try again Code: [Select]

Convert epoch date to human readable date format in a log file.

Switch to the previous branch used in git(1)
Very useful if you keep switching between the same two branches all the time.

Compare / diff two images
Outputs the number of different pixels. 2 params to increase tolerance: * thumbnails size * fuzz, the color distance tolerance See http://en.positon.org/post/Compare-/-diff-between-two-images for more details.

distribution specific information

SMTP Analysis
This works just as well for SMTP. You could run this on your mail server to watch e-mail senders and recipients: tcpdump -l -s0 -w - tcp dst port 25 | strings | grep -i 'MAIL FROM\|RCPT TO'

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"


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