Commands by light13 (4)

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Filter IP's in apache access logs based on use
The first sort is necessary for ips in a list to be actually unique.

Add page numbers to a PDF
Put this code in a bash script. The script expects the PDF file as its only parameter. It will add a header to the PDF containing the page numbers and output it to a file with the suffix "-header.pdf" Requires enscript, ps2pdf and pdftk.

Prints line numbers
If you don't have nl on your system, this achieves a similar effect, the default behavior in nl is to not number blank lines, but this does.

Make a dedicated folder for each zip file
${f%*.zip} strips off the extension from zip filenames

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

calculate the total size of files in specified directory (in Megabytes)

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" }

Speed up the keyboard repeat rate in X server

Search for a process by name
ps and grep is a dangerous combination -- grep tries to match everything on each line (thus the all too common: grep -v grep hack). ps -C doesn't use grep, it uses the process table for an exact match. Thus, you'll get an accurate list with: ps -fC sh rather finding every process with sh somewhere on the line.

randomize hostname and mac address, force dhcp renew. (for anonymous networking)
this string of commands will release your dhcp address, change your mac address, generate a new random hostname and then get a new dhcp lease.


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