Commands using grep (1,935)

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check open ports without netstat or lsof

Get video information with ffmpeg
I used an flv in my example, but it'll work on any file ffmpeg supports. It says it wants an output file, but it tells what you want to know without one.

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" }

Get MD5 checksum from a pipe stream and do not alter it

List the libraries used by an application
For example, you need to make a copy of all the libraries that a certain application uses, with this command you can list and copy them.

Null a file with sudo

Download song from youtube for import into itunes (m4a format)
Last argument is the youtube link. Requires ffmpeg

Prints a file leaving out all blank lines and comment-only lines
Does not print any line that either: - is empty - contains only spaces or tabs - starts with # - starts with spaces/tabs followed by a #

Display top 5 processes consuming CPU

Create user add lines from partial passwd file
Handy if you are installing a new server or recovering an old one and you have a passwd file with the accounts you want to add to the server. If you edit the file so that only the accounts that you want to add are left this line will spit out the correct useradd lines. The uid, gecos and shell will be preserved.


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