Commands using grep (1,935)

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Extract audio stream from an video file using mencoder
This command extracts the audio stream of the video in $file and stores it in a file where the original suffix is changed to .mp3

convert ascii string to hex
just a bit simpler

How to pull out lines between two patterns
This command will display all lines between 2 patterns: word-a and word-b useful for grepping command outputs from file

Show sorted list of files with sizes more than 1MB in the current dir
Taken from here: http://linsovet.com/directory-usage-size-sorted-list

Filter IP's in apache access logs based on use
Show's per IP of how many requests they did to the Apache webserver

Display a wave pattern
Purely frivolous - print a sine/cosine curve to the console - the width varies as it progresses. Ctrl-C to halt.

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" }

Listen to a file
replace "/usr/src/linux/kernel/signal.c" with any file you want and listen to its output ! :P you can also replace "cat" with "echo" or anything you can come up with have fun :-}

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"

Follow tail by name (fix for rolling logs with tail -f)
If you use 'tail -f foo.txt' and it becomes temporarily moved/deleted (ie: log rolls over) then tail will not pick up on the new foo.txt and simply waits with no output. 'tail -F' allows you to follow the file by it's name, rather than a descriptor. If foo.txt disappears, tail will wait until the filename appears again and then continues tailing.


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