Commands using set (54)

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For finding out if something is listening on a port and if so what the daemon is.

Don't spam root. Log your cronjob output to syslog
This command will log the output of your simple cronjobs to syslog, and syslog will take it from there. Works great for monitoring scripts which only produce simple output. Advantages: * This can be used by regular users, without modifying system files like /etc/syslog.conf * Reduce cron spam to root@localhost (Please stop spaming the sysadmins) * Uses common tools like syslog (and logrotate) so that you don't need to maintain yet another krufty logfile. * Still ensures that the output is logged somewhere, for posterity. Perhaps it's stored the secure, central syslog server, for example. * Seems to work fine on Ubuntu, CentOS, FreeBSD & MacOSX

Get all shellcode on binary file from objdump
Tired copy paste to get opcode from objdump huh ? Get more @ http://gunslingerc0de.wordpress.com

Create a script of the last executed command
Sometimes commands are long, but useful, so it's helpful to be able to make them permanent without having to retype them. An alternative could use the history command, and a cut/sed line that works on your platform. $history -1 | cut -c 7- > foo.sh

Read the output of a command into the buffer in vim
This will append the output of "command" to whatever file you're currently editing in vim. Who else has good vim tricks? :)

convert ascii string to hex
Even adds a newline.

Monitor memory usage
Monitor with watch command and vmstat, memory usage

Keep a copy of the raw Youtube FLV,MP4,etc stored in /tmp/
Certain Flash video players (e.g. Youtube) write their video streams to disk in /tmp/ , but the files are unlinked. i.e. the player creates the file and then immediately deletes the filename (unlinking files in this way makes it hard to find them, and/or ensures their cleanup if the browser or plugin should crash etc.) But as long as the flash plugin's process runs, a file descriptor remains in its /proc/ hierarchy, from which we (and the player) still have access to the file. The method above worked nicely for me when I had 50 tabs open with Youtube videos and didn't want to have to re-download them all with some tool.

recursive search and replace old with new string, inside files
Search and replace recursively. :-) Shorter and simpler than the others. And allows more terms: replace old new [old new ...] -- `find -type f`

Random file naming


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