Commands using su (16)

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Execute a command at a given time
This is an alternative to cron which allows a one-off task to be scheduled for a certain time.

delay execution of a command that needs lots of memory and CPU time until the resources are available
[ 2000 -ge "$(free -m | awk '/buffers.cache:/ {print $4}')" ] returns true if less than 2000 MB of RAM are available, so adjust this number to your needs. [ $(echo "$(uptime | awk '{print $10}' | sed -e 's/,$//' -e 's/,/./') >= $(grep -c ^processor /proc/cpuinfo)" | bc) -eq 1 ] returns true if the current machine load is at least equal to the number of CPUs. If either of the tests returns true we wait 10 seconds and check again. If both tests return false, i.e. 2GB are available and machine load falls below number of CPUs, we start our command and save it's output in a text file. The ( ( ... ) & ) construct lets the command run in background even if we log out. See http://www.commandlinefu.com/commands/view/3115/ .

list block devices
Shows all block devices in a tree with descruptions of what they are.

Load file into RAM (cache) for faster accessing for repeated usage
Best result when file size less than half of RAM size

Regenerate the /etc/mtab file

Erase a word
hit BACKSPACE more than once to delete more words

Find the package that installed a command

Search for in which package the specified file is included.

Change a specific value in a path
Awk replaces the value of a specific field while retaining the field separator "/" .

archlinux: find more commands provided by the package owning some command
uses the pkgfile command (part of the community repository), highly suggested.


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