Commands by myahia (2)

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journalctl -f
a tail -f variant of systemd journal. Follow the most recent updates or if events are appended to the journal

Force GNU/Linux keyboard settings, layout and configuration
Bash snippet to force GNU/Linux keyboard settings, layout and configuration. Usefull when some GNU/Linux distributions such as *Ubuntu's store only limited configation options due to demonstration purposes on LiveUSB or Live persistent devices. Overcomes the English QWERTY to French AZERTY settings failure. Code bash en ligne de commande pour forcer l'adoption du clavier AZERTY sur les cl? USB bootable en Ubuntu.

Prevent an IPv6 address on an interface from being used as source address of packets.
If two or more IPv6 addresses are assigned to an interface, apply this command to all but the address that you want to use as the source address of outbound packets. This is Linux-specific and requires the iproute package, or equivalent for your distribution.

Remove a file whose name begins with a dash ( - ) character
Using the redundant ./ directory information prevents the dash from occurring at the beginning of the filename, and being interpreted as an option of the rm command. Also works using: $ rm -- -filename

DELETE all those duplicate files but one based on md5 hash comparision in the current directory tree
This one-liner will the *delete* without any further confirmation all 100% duplicates but one based on their md5 hash in the current directory tree (i.e including files in its subdirectories). Good for cleaning up collections of mp3 files or pictures of your dog|cat|kids|wife being present in gazillion incarnations on hd. md5sum can be substituted with sha1sum without problems. The actual filename is not taken into account-just the hash is used. Whatever sort thinks is the first filename is kept. It is assumed that the filename does not contain 0x00. As per the good suggestion in the first comment, this one does a hard link instead: $ find . -xdev -type f -print0 | xargs -0 md5sum | sort | perl -ne 'chomp; $ph=$h; ($h,$f)=split(/\s+/,$_,2); if ($h ne $ph) { $k = $f; } else { unlink($f); link($k, $f); }'

Find all active ip's in a subnet
nmap for windows and other platforms is available on developer's site: http://nmap.org/download.html nmap is robust tool with many options and has various output modes - is the best (imho) tool out there.. from nmap 5.21 man page: -oN/-oX/-oS/-oG : Output scan in normal, XML, s|

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"

Generate Sha1, MD5 hash using echo
This is mostly for my own notes but this command will compute a md5 message digest from the command line. You can also replace md5sum with other checksum commands (e.g., sha1sum)

Clean your broken terminal
If something fracks up your terminal, just type in 'reset' and everything should be good again.

Print stack trace of a core file without needing to enter gdb interactively
The pstack command prints a stack trace of running processes without needing to attach a debugger, but what about core files? The answer, of course, is to use this command. Usage: gdbbt program corefile

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