Commands by Code_Bleu (8)

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Complete TCP Handshake on a given host-port
Try to perform a fully TCP 3 way handshake on for a given host-port with a timeout of 1s.

Create a single-use TCP (or UDP) proxy
Redirect the local port 2000 to the remote port 3000. The same but UDP: $ nc -u -l -p 2000 -c "nc -u example.org 3000" It may be used to "convert" TCP client to UDP server (or viceversa): $ nc -l -p 2000 -c "nc -u example.org 3000"

create iso image from a directory
create iso image from directory . Usefull for virtualised machine To create CD ISO image of directories that contain long file name or non-8.3 format (particularly if you want to burn the CD image for use in Windows system), use the -J option switch that generates Joliet directory records in addition to regular iso9660 file names. For example, to create CD image of Vista SP1 directory: mkisofs -o VitaSP1.iso -J VistaSP1

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

concatenate compressed and uncompressed logs
with zcat force option it's even simpler.

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"

Rename files to be all in CAPITALS
Simple bash/ksh/sh command to rename all files from lower to upper case. If you want to do other stuff you can change the tr command to a sed or awk... and/or change mv to cp....

netstat with group by (ip adress)
Same as the rest, but handle IPv6 short IPs. Also, sort in the order that you're probably looking for.

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"

List all installed Debian packages
Should work on all systems that use dpkg and APT package management.


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