Commands by kurt (1)

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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shell bash iterate number range with for loop

Find chronological errors or bad timestamps in a Subversion repository
Lists revisions in a Subversion repository with a timestamp that doesn't follow the revision numbering order. If everything is OK, nothing is displayed.

Uptime in minute

Perl Simple Webserver
First we accept a socket and fork the server. Then we overload the new socket as a code ref. This code ref takes one argument, another code ref, which is used as a callback. The callback is called once for every line read on the socket. The line is put into $_ and the socket itself is passed in to the callback. Our callback is scanning the line in $_ for an HTTP GET request. If one is found it parses the file name into $1. Then we use $1 to create an new IO::All file object... with a twist. If the file is executable("-x"), then we create a piped command as our IO::All object. This somewhat approximates CGI support. Whatever the resulting object is, we direct the contents back at our socket which is in $_[0].

pop-up messages on a remote computer
Run this command when you are physically at the computer you wish to send pop-up messages to. Then when you ssh in to it, you can do this: echo "guess who?" > commander guess who? will then pop up on the screen for a few moments, then disappear. You will need to create the commander file first. I mess with my wife all the time with this. i.e. echo "You have given the computer a virus. Computer will be rendered useless in 10 seconds." > commander lol

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" }

See a full list of compiler defined symbols
From .

Multi line grep using sed and specifying open/close tags
This line does not include your closing tag in the output.

tcmdump check ping
capture only ping echo requests with tcpdump

Remove a range of lines from a file

Stay in the loop…

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