Commands by devrick0 (1)

  • It takes over 5 seconds to scan a single port on a single host using nmap time (nmap -p 80 192.168.1.1 &> /dev/null) real 0m5.109s user 0m0.102s sys 0m0.004s It took netcat about 2.5 minutes to scan port 80 on the class C time (for NUM in {1..255} ; do nc -w 1 -z -v 192.168.1.${NUM} 80 ; done &> /dev/null) real 2m28.651s user 0m0.136s sys 0m0.341s Using parallel, I am able to scan port 80 on the entire class C in under 2 seconds time (seq 1 255 | parallel -j255 'nc -w 1 -z -v 192.168.1.{} 80' &> /dev/null) real 0m1.957s user 0m0.457s sys 0m0.994s


    3
    seq 1 255 | parallel -j+0 'nc -w 1 -z -v 192.168.1.{} 80'
    devrick0 · 2011-06-11 14:40:51 0

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands


Check These Out

Write a bootable Linux .iso file directly to a USB-stick
Writes hybrid ISO directly to USB stick; replace /dev/sdb with USB device in question and the ISO image link with the link of your choice

Console clock
Shows a simple clock in the console -t param removes the watch header Ctrl-c to exit

detect partitions
Shows all block devices in a tree with descruptions of what they are.

find text in a file
this will find text in the directory you specify and give you line where it appears.

Display network pc "name" and "workgroup"
Checks for PC samba name and workgroup. Works fine for Windows hosts and Linux/UNIX PCs running Samba.

Retry the previous command until it exits successfully
Repeat the previously used command (!!) until it exits with a success code (0). To put a delay between attempts you could do something like $ until !!; do sleep 5; done to wait 5 seconds after each attempt.

Simplification of "sed 'your sed stuff here' file > file2 && mv file2 file"

Rip DVD to YouTube ready MPEG-4 AVI file using mencoder
Rip DVD to YouTube ready AVI file, using MPEG-4 video codec and MP3 audio codec. Resizes to 320x240 and deinterlaces as needed.

Remove all the files except abc in the directory
This is for zsh with extended globbing.

checking space availabe on all /proc/mounts points (using Nagios check_disk)
More info here: http://nagioswiki.com/wiki/index.php/Checking_/proc/mounts_on_remote_server


Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for: