Commands using cat (514)

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Audible warning when a downloading is finished
This command can be set as an alias in ~/.bashrc For example (in my case) I have : alias watchDl='while [ "$(ls $filePart)" != "" ]; do sleep 5; done; mpg123 /home/.../warning.mp3" ' Then I just need to - initialize filePart (e.g. filePart="*bigFile*rar.part") - launch watchDl

backup directory. (for bash)

Simplified video file renaming
I used this when I had a directory of movies from a camera. I wanted to watch a little of each movie, then rename it depending on what was in the movie. This did the trick for me.

mysql bin log events per minute
shows number of mysql bin log events (which are mysql server events) per minute, useful to check stress times postmortem

Make vim open in tabs by default (save to .profile)
I always add this to my .profile rc so I can do things like: "vim *.c" and the files are opened in tabs.

which program is this port belongs to ?
Sometimes you need to use a port that is already opened by some program , and you don't know who to "kill" for it to release - so, now you do !

edit, view or execute last modified file with a single key-press
Copy this function to command line, press 'Enter' 'f'' 'Enter' to execute (sentence on the left written only for newbies). Hint 'e|x|v|1..9' in front of displayed last modified file name means: "Press 'e' for edit,'x' for execute,'v' for view or a digit-key '1..9' to touch one file from the recent files list to be last modified" and suggested (hidden files are listed too, else remove 'a' from 'ls -tarp' statement if not intended). If you find this function useful you can then rename it if needed and append or include into your ~/.bashrc config script. With the command $ . ~/.bashrc the function then can be made immediately available. In the body of the function modifications can be made, i.e. replaced joe editor command or added new option into case statement, for example 'o) exo-open $h;;' command for opening file with default application - or something else (here could not be added since the function would exceed 255 chars). To cancel execution of function started is no need to press Ctrl-C - if the mind changed and want to leave simple Enter-press is enough. Once defined, this function can with $ typeset -f f command be displayed in easy readable form

Running a command at a specific time

Find the fastest server to disable comcast's DNS hijacking
Comcast is an ISP in the United States that has started hijacking DNS requests as a "service" for its customers. For example, in Firefox, one used to be able to do a quick "I'm Feeling Lucky" Google search by typing a single word into the URL field, assuming the word is not an existing domain when surrounded by www.*.com. Comcast customers never receive the correct NX (non-existent domain) error from DNS. Instead, they are shown a page full of advertising. There is a way to "opt out" from their service, but that requires having the account password and the MAC address of your modem handy. For me, it was easier just to set static DNS servers. But the problem is, which ones to choose? That's what this command answers. It'll show you the three _non-hijacked_ Comcast DNS servers that are the shortest distance away. Perhaps you don't have Comcast (lucky you!), but hopefully this command can serve as an example of using netselect to find the fastest server from a list. Note that, although this example doesn't show it, netselect will actually perform the uniq and DNS resolution for you. Requires: netselect, curl, sort, uniq, grep

Resize all JPEGs in a directory
This command requires the imagemagick libraries and will resize all files with the .jpg extension to a width of 1024 pixels and will keep the same proportions as the original image.


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