Commands by pyrho (5)

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easily trace all Nginx processes
Nginx (and other webservers like Apache) can be awkward to trace. They run as root, then switch to another user once they're ready to serve web pages. They also have a "master" process and multiple worker processes. The given command finds the process IDs of all Nginx processes, joins them together with a comma, then traces all of them at once with "sudo strace." System trace output can be overwhelming, so we only capture "networking" output. TIP: to kill this complex strace, do "sudo killall strace". Compare with a similar command: http://www.commandlinefu.com/commands/view/11918/easily-strace-all-your-apache-processes

Create a quick back-up copy of a file
Uses shell expansion to create a back-up called file.txt.bak

ShellCheck all the bash/sh script under a specific directory excluding version control
This is a commodity one-liner that uses ShellCheck to assure some quality on bash and sh scripts under a specific directory. It ignores the files in .git directory. Just substitute "./.git/*" with "./.svn/*" for older and booring centralized version control. Just substitute ShellCheck with "rm" if your scripts are crap and you want to get rid of them :)

Consolle based network interface monitor
ethstatus part of ethstatus package, is a consolle based monitor for network interfaces. Nicely display on screen a real time summary about bandwidth, speed and packets.

Kill all processes that listen to ports begin with 50 (50, 50x, 50xxx,...)
Run netstat as root (via sudo) to get the ID of the process listening on the desired socket. Use awk to 1) match the entry that is the listening socket, 2) matching the exact port (bounded by leading colon and end of column), 3) remove the trailing slash and process name from the last column, and finally 4) use the system(…) command to call kill to terminate the process. Two direct commands, netstat & awk, and one forked call to kill. This does kill the specific port instead of any port that starts with 50. I consider this to be safer.

Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

Block all FaceBook traffic

List all commands present on system

Blank/erase a DVD-RW

Live stream a remote desktop over ssh using only ffmpeg
Play with the framerate option '-r' to scale back bandwidth usage. The '-s' option is the captured screan area, not the rescaled size. If you want to rescale add a second '-s' option after '-i :0'. Rescaling smaller will also decrease bandwidth.


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