Commands by hadifarnoud (3)

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Get the SAN (subjectAltName) of a site's certificate.
Based on http://stackoverflow.com/questions/13127352/checking-alternative-names-for-a-san-ssl-cert Replace "facebook.com" with the desired hostname.

geoip lookup

add all files not under version control to repository
This should handle whitespaces well and will not get confused if your filenames have "?" in them

take a screenshot of a webpage

create an incremental backup of a directory using hard links
dname is a directory named something like 20090803 for Aug 3, 2009. lastbackup is a soft link to the last backup made - say 20090802. $folder is the folder being backed up. Because this uses hard linking, files that already exist and haven't changed take up almost no space yet each date directory has a kind of "snapshot" of that day's files. Naturally, lastbackup needs to be updated after this operation. I must say that I can't take credit for this gem; I picked it up from somewhere on the net so long ago I don't remember where from anymore. Ah, well... Systems that are only somewhat slicker than this costs hundreds or even thousands of dollars - but we're HACKERS! We don't need no steenkin' commercial software... :)

Reinstall a Synology NAS without loosing any data from commandline.
Seen many questions how-to reinstall synology nas dsm without loosing data, here you go. Wait for a few min and then head over to http://nasip and setup your fresh installed nas.

Send pop-up notifications on Gnome
The title is optional. Options: -t: expire time in milliseconds. -u: urgency (low, normal, critical). -i: icon path. On Debian-based systems you may need to install the 'libnotify-bin' package. Useful to advise when a wget download or a simulation ends. Example: $ wget URL ; notify-send "Done"

Most simple way to get a list of open ports

Copy the sound content of a video to an mp3 file
-vn removes tha video content, the copy option tells ffmpeg to use the same codec for generating the output

Use default value if unassigned
Will use variable value (for variable $my_dir, in this case), an assign a default value if there is none.


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