Commands by RapazP (1)

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Start COMMAND, and kill it if still running after 5 seconds

Efficient count files in directory (no recursion)
$ time perl -e 'if(opendir D,"."){@a=readdir D;print $#a - 1,"\n"}' 205413 real 0m0.497s user 0m0.220s sys 0m0.268s $ time { ls |wc -l; } 205413 real 0m3.776s user 0m3.340s sys 0m0.424s ********* ** EDIT: turns out this perl liner is mostly masturbation. this is slightly faster: $ find . -maxdepth 1 | wc -l sh-3.2$ time { find . -maxdepth 1|wc -l; } 205414 real 0m0.456s user 0m0.116s sys 0m0.328s ** EDIT: now a slightly faster perl version $ perl -e 'if(opendir D,"."){++$c foreach readdir D}print $c-1,"\n"' sh-3.2$ time perl -e 'if(opendir D,"."){++$c foreach readdir D}print $c-1,"\n"' 205414 real 0m0.415s user 0m0.176s sys 0m0.232s

Kill any lingering ssh processes
Also ignoring "sshd" server is necessary since you should not kill ssh server processes.

set a reminder for 5 days in the future
setup for reminder in 5 days, added the date in the future. To run a job at 4pm three days from now, you would do at 4pm + 3 days, to run a job at 10:00am on July 31, you would do at 10am Jul 31 and to run a job at 1am tomorrow, you would do at 1am tomorrow.

Display the output of a command from the first line until the first instance of a regular expression.
Slightly simpler version of previous sed command that does the same thing. In this case, the output will stop at the command, and the entire command will be terminated as well, instead of proceeding through the whole file.

Git diff last two commits
How about this one ?

ZSH prompt. ':)' after program execution with no error, ':(' after failure.
sorry for my english

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

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"

BourneShell: Go to previous directory
cd - would return to the previous directory of your cd command. NB: previous dir is always stored in $OLDPWD variable.

Stay in the loop…

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