Commands tagged regexp (5)

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copy partition table from /dev/sda to /dev/sdb

Short one line while loop that outputs parameterized content from one file to another
There is a common command for outputting a field or list of fields from each line in a file. Why wouldn't you just use cut?

convert a line to a space

Look at your data as a greymap image.
Keep width to a power of 2 to see patterns emerge. 512 is good. So is 4096 for huge maps. PNM headers are super basic. http://netpbm.sourceforge.net/doc/pbm.html

pretend to be busy in office to enjoy a cup of coffee
Not as taxing on the CPU.

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" }

A fun thing to do with ram is actually open it up and take a peek. This command will show you all the string (plain text) values in ram

list files recursively by size

Change active bond slave
This forces a bonded interface to switch to another slave in the bond as its active slave.

Run the last command as root
Same as `sudo !!`. If you do not have permission to be sudo or sudo does not installed on your system, you can use this.


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