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This assumes you have the 'rpm', 'rpm2cpio' and 'cpio' packages installed. This will extract the contents of the RPM package to your current directory. This is useful for working with the files that the package provides without installing the package on your system. Might be useful to create a temporary directory to hold the packages before running the extraction:
$ mkdir /tmp/new-package/; cd /tmp/new-package
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"
}
can be used within a script to configure iptables for example:
iface=$2
inet_ip=`ifconfig "$iface" | grep inet | cut -d: -f2 | cut -d ' ' -f1`
ipt="sudo /sbin/iptables"
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$ipt -A INPUT -i $iface ! -f -p tcp -s $UL -d $inet_ip --sport 1023: --dport 3306 -m state --state NEW,ESTABLISHED -j ACCEPT
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$ipt -A OUTPUT -o $iface -p tcp -s $inet_ip -d $UL --sport 3306 --dport 1023: -m state --state ESTABLISHED,RELATED -j ACCEPT
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the block of the loop is useful whenever you have huge junks of similar jobs, e.g., convert high res images to thumbnails, and make usage out of all the SMP power on your compute box without flooding the system.
note: c is used as counter and the random sleep
$ r=`echo $RANDOM%5 |bc`; echo "sleep $r"; sleep $r
is just used as a dummy command.
If somehow if you get more than 1 same name rpm package install, then it cannot be removed by using simple rpm -e as it gives you more than one rpm matches error. The --matches will help to remove all the same name rpm packages.
For slow flash memory (cheap thumb drive), ext4 is the fastest stable file system for all use cases with no relevant exception:
http://www.linuxplanet.com/linuxplanet/tutorials/7208/1
Since we can usually dispense with the benefits of a journal for this type of storage, this is a way to achieve the least awful I/O-speed.
Disabling the journal for an existing ext4 partition can be achieved using
$ tune2fs -O ^has_journal /dev/sdXN
Note that it is often recommended to format removable flash media with ext2, due to the lack of a journal. ext4 has many advantages over ext2 even without the journal, with much better speed as one of the consequences. So the only usecase for ext2 would be compatibility with very old software.
After typing the command below, you will be greeted with nothing. press the up arrow to find the previous command you typed, press enter. repeat this as many times as you need, then hit CTRL-Z and press enter to save to the 'batchfilename.bat' file.
