Commands by timrand (3)

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Use top to monitor only all processes with the same name fragment 'foo'
top accecpts a comma separated list of PIDs.

urldecoding
$ echo "http%3A%2F%2Fwww.google.com" | sed -e's/%\([0-9A-F][0-9A-F]\)/\\\\\x\1/g' | xargs echo -e http://www.google.com $ Works under bash on linux. just alter the '-e' option to its corresponding equivalence in your system to execute escape characters correctly.

Setting reserved blocks percentage to 1%
According to tune2fs manual, reserved blocks are designed to keep your system from failing when you run out of space. Its reserves space for privileged processes such as daemons (like syslogd, for ex.) and other root level processes; also the reserved space can prevent the filesystem from fragmenting as it fills up. By default this is 5% regardless of the size of the partition. http://www.ducea.com/2008/03/04/ext3-reserved-blocks-percentage/

live netcat network throughput test
On the another machine write this command. pv -r /dev/zero | nc 192.168.1.1 7777 It will show live throughput between two machine.The destination machine ip is at our example 192.168.1.1 You must multiply by 8 for the network calculation. You must install pv and netcat commands for this commands usage. kerim@bayner.com http://www.bayner.com/

Capture FTP Credentials and Commands

Expand shortened URLs
curl(1) is more portable than wget(1) across Unices, so here is an alternative doing the same thing with greater portability. This shell function uses curl(1) to show what site a shortened URL is pointing to, even if there are many nested shortened URLs. This is a great way to test whether or not the shortened URL is sending you to a malicious site, or somewhere nasty that you don't want to visit. The sample output is from: $ expandurl http://t.co/LDWqmtDM

Remove specific versions of old kernels (Ubuntu/Debian)
If, for example, you want to remove all kernels and headers but the last three versions, you can't use one of that magic all-in-one "remove old stuff" commands. With this simple but elegant command you can remove a range of versions, or a list of versions with e.g. {14,16,20}.

Calculates the number of physical cores considering HyperThreading in AWK
Check whether hyperthreading is enabled or not. a better solution as nproc should work on all OS with awk

Send a local file via email
if "mail -a" fail, try "mutt -a" or "nail -a"

Remove a range of lines from a file


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