Commands by alleen1 (1)

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Write on the console without being registered
just use a space to prevent commands from being recorded in bash's history on most systems

Write a shell script that removes files that contain a string
Deletes files in the current directory or its subdirectories that match "regexp" but handle directories, newlines, spaces, and other funky characters better than the original #13315. Also uses grep's "-q" to be quiet and quit at the first match, making this much faster. No need for awk either.

Create a directory and change into it at the same time
How often do you make a directory (or series of directories) and then change into it to do whatever? 99% of the time that is what I do. This BASH function 'md' will make the directory path then immediately change to the new directory. By using the 'mkdir -p' switch, the intermediate directories are created as well if they do not exist.

Use top to monitor only all processes with the same name fragment 'foo'
Like command 10870, but no need for sed

Generate a random password 30 characters long

Prepend a text to a file.
Using the sed -i (inline), you can replace the beginning of the first line of a file without redirecting the output to a temporary location.

Capture video of a linux desktop
This will grab the image from desktop, starting with the upper-left corner at x=100, y=200 with a width and height of 1024?768.

Convert all WMF images to SVG recursively ignoring file extension case
This assumes you have the package installed necessary for converting WMF files. On my Ubuntu box, this is libwmf-bin. I used this command, as libwmf is not on my wife's iMac, so I archived the directories containing the WMF files from OS X, ran them on my Ubuntu box, archived the resulting SVGs, and sent them back to her. Quick, simple and to the point. Searches directories recursively looking for extensions ignoring case. This is much more readable and clean than -exec for find. The while loop also gives further flexibility on complex logic. Also, although there is 'wmf2svg --auto', it expects lowercase extensions, and not uppercase. Because I want to ignore case, I need to use the -o option instead. Works in ZSH and BASH. Haven't tested in other shells.

Print text string vertically, one character per line.

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.


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