Commands tagged sed (376)

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Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Format partition with ext4 but without a journal
For slow flash memory (cheap thumb drive), ext4 is the fastest stable file system for all use cases with no relevant exception: http://www.linuxplanet.com/linuxplanet/tutorials/7208/1 Since we can usually dispense with the benefits of a journal for this type of storage, this is a way to achieve the least awful I/O-speed. Disabling the journal for an existing ext4 partition can be achieved using $ tune2fs -O ^has_journal /dev/sdXN Note that it is often recommended to format removable flash media with ext2, due to the lack of a journal. ext4 has many advantages over ext2 even without the journal, with much better speed as one of the consequences. So the only usecase for ext2 would be compatibility with very old software.

Monitor open connections for httpd including listen, count and sort it per IP
It's not my code, but I found it useful to know how many open connections per request I have on a machine to debug connections without opening another http connection for it. You can also decide to sort things out differently then the way it appears in here.

Google text-to-speech in mp3 format
same but redirecting to player and putting whaever text line.. works on my ubuntu machine ...

Take a screenshot of a login screen
when using Gnome or KDE, you will have a hard time getting a screenshot of something like a login screen, or any other screen that occurs before the desktop environment is up and monitoring the printscreen key. (this probably applies for other DEs as well, but I haven't used them) What this command is meant to do is take a screenshot of an X window using a command you can run from your virtual terminals (actual text terminals, not just an emulator) To do this: Press CTRL+ALT+F1 to go to a virtual (text) terminal once your login window comes up Login to the virtual terminal and enter the command (you'll have to type it in) You should now have a file called screenshot.png in your home directory with your screenshot in it. For those of you who are new to the virtual terminal thing, you can use CTRL+ALT+F7 to get back to your regular GUI From http://www.gnome.org

shell function to make gnu info act like man.
For those who hate navigating info pages, a shell function which will dump the contents to stdout, then page it through less, thus acting like 'man'.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Rebuild a Delimited File with a Unique Delimiter
Useful for CSV files. In the command, the file in question is comma delimited but contains double quoted fields containing commas and contains no @ symbols (as confirmed with http://www.commandlinefu.com/commands/view/9998/delimiter-hunting). This command converts the delimiting commas to @s while preserving the commas in the fields using the "uniqueString" to mark the ends of lines.

c_rehash replacement
When you don't have c_rehash handy. Really simple - if you have a .pem file that doesn't really contain a x509 cert (let's say, newreq.pem), it will create a link, simply called '.0', pointing to that file.

du command without showing other mounted file systems


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