Commands by omish_man (2)

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How to secure delete a file
Instead, install apt-get install secure-delete and you can use: -- srm to delete file and directory on hard disk -- smem to delete file in RAM -- sfill to delete "free space" on hard disk -- sswap to delete all data from swap

check open ports without netstat or lsof

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" }

Delete an IPtable rules based on row number

list all opened ports on host

Show a config file without comments
Shows a file without comments (at least those starting by #) - removes empty lines - removes lines starting by # or "some spaces/tabs then #'" Useful when you want to quickly see what you have to customize on a freshly installed application without reading the comments that sometimes are a full 1000 lines documentation :) While posting, I saw this http://www.commandlinefu.com/commands/view/1041/display-contents-of-a-file-wo-any-comments-or-blank-lines But it's dirty and incomplete, to my mind My original goal was to remove lines like "\t*#" but I can't figure out how to do a egrep '\t' on a command-line. Two workarounds if needed: $egrep -v 'press control + V then TAB then #' /your/file or $egrep -v -f some_file /your/file #where some_file contains what you want to exclude, example a really inserted TAB

Lists all clients of a Squid proxy
Generates the list of clients (IPs addresses) that have used the Squid webproxy according to the most recent log. Every IP appears only once in the list.

Find dupe files by checking md5sum

Unlock more space form your hard drive
This command changes the reserved space for privileged process on '/dev/sda' to 1 per cent.

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.


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