Commands tagged awk (348)

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To convert **.wav to **.mp3 using LAME running one process per CPU core run:

identify NEEDED sonames in a path
This works in combination with http://www.commandlinefu.com/commands/view/10496/identify-exported-sonames-in-a-path as it reports the NEEDED entries present in the files within a given path. You can then compare it with the libraries that are exported to make sure that, when cross-building a firmware image, you're not bringing in dependencies from the build host. The short version of it as can be seen in the same output is $ scanelf -RBnq -F "+n#f" $1 | tr ',' '\n' | sort -u

Block known dirty hosts from reaching your machine
Blacklisted is a compiled list of all known dirty hosts (botnets, spammers, bruteforcers, etc.) which is updated on an hourly basis. This command will get the list and create the rules for you, if you want them automatically blocked, append |sh to the end of the command line. It's a more practical solution to block all and allow in specifics however, there are many who don't or can't do this which is where this script will come in handy. For those using ipfw, a quick fix would be {print "add deny ip from "$1" to any}. Posted in the sample output are the top two entries. Be advised the blacklisted file itself filters out RFC1918 addresses (10.x.x.x, 172.16-31.x.x, 192.168.x.x) however, it is advisable you check/parse the list before you implement the rules

Block all IPv4 addresses that has brute forcing our ssh server
For ipv6 use: grep -oE "\b([0-9A-Fa-f]{1,4}:){7}[0-9A-Fa-f]{1,4}\b"

Copy via tar pipe while preserving file permissions (run this command as root!)
It's the same like 'cp -p' if available. It's faster over networks than scp. If you have to copy gigs of data you could also use netcat and the tar -z option in conjunction -- on the receiving end do: # nc -l 7000 | tar -xzvpf - ...and on the sending end do: # tar -czf - * | nc otherhost 7000

Commandline document conversion with Libreoffice
In this example, the docx gets converted to Open Document .odt format. For other formats, you'll need to specify the correct filter (Hint: see "Comments" link below for a nice list).

My Git Tree Command!
this creates a tree of your branch merges. very useful if you want to follow the features you add.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Silently ensures that a FS is mounted on the given mount point (checks if it's OK, otherwise unmount, create dir and mount)
In my example, the mount point is /media/mpdr1 and the FS is /dev/sdd1 /mountpoint-path = /media/mpdr1 filesystem=/dev/sdd1 Why this command ? Well, in fact, with some external devices I used to face some issues : during data transfer from the device to the internal drive, some errors occurred and the device was unmounted and remounted again in a different folder. In such situations, the command mountpoint gave a positive result even if the FS wasn't properly mounted, that's why I added the df part. And if the device is not properly mounted, the command tries to unmount, to create the folder (if it exists already it will also work) and finally mount the FS on the given mount point.

List all authors of a particular git project
This should work even if the output format changes.


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