Commands by duxklr (3)

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Update zone file Serial numbers
Will edit *.db files in the same directory with todays date. Useful for doing a mass update to domains on a nameserver, adding spf records, etc. Looks for a string starting with 200 or 201 followed by 7 numbers, and replaces with todays date. This won't overwrite Ip's but i would still do some double checking after running this. Make sure your server's date is correct, otherwise insert your own serial number. $rndc reload should usually follow this command.

Perl Command Line Interpreter
My Programming Languages professor assigned my class a homework assignment where we had to write a Perl interpreter using Perl. I really like Python's interactive command line interpreter which inspired this Perl script.

Generate RSA private key and self-signed certificate
This will create, in the current directory, a file called 'pk.pem' containing an unencrypted 2048-bit RSA private key and a file called 'cert.pem' containing a certificate signed by 'pk.pem'. The private key file will have mode 600. !!ATTENTION!! ==> this command will overwrite both files if present.

External IP (raw data)
can be used in script like : echo $(wget -qO- http://utils.admin-linux.fr/ip.php)

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.

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" }

The Chromium OS rootfs is mounted read-only. In developer mode you can disable the rootfs verification, enabling it to be modified.

Bash logger

Show permissions of current directory and all directories upwards to /
NB not 'namei -m .', as it slices the path you give it.

List Threads by Pid along with Thread Start Time
This command will list all threads started by a particular pid along with the start time of each thread. This is very valuable when diagnosing thread leaks.


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