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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"

Get all links from commandlinefu front page
You need to install WWW::Mechanize Perl module with # cpan -i WWW::Mezchanize or by searching mechanize | grep perl in your package manager With this command, you can get forms, images, headers too

CPU architecture details
This command list all CPU technical infos.

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.

Fix Ubuntu's Broken Sound Server
Ever since the switch to pulseaudio, Ubuntu users including myself have found themselves with no sound intermittently. To fix this, just use this command and restarts firefox or mplayer or whatever.

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"

Edit the Last Changed File

SMTP Analysis
This works just as well for SMTP. You could run this on your mail server to watch e-mail senders and recipients: tcpdump -l -s0 -w - tcp dst port 25 | strings | grep -i 'MAIL FROM\|RCPT TO'

Empty a file

recursive reset file/dir perms
Good for fixing web permissions. You might also want to do something like this and skip files or directories that begin with a period: $ find public_html/stuff -not -name ".*" \( -type d -exec chmod 755 {} + -o -type f -exec chmod 644 {} + \) ...or include a special case for scripts: $ find public_html/stuff -type d -exec chmod 755 {} + -or -type f -name "*.pl" -exec chmod 755 {} + -or -exec chmod 644 {} +


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