Commands tagged canon (3)

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Prints a file leaving out all blank lines and comment-only lines
Does not print any line that either: - is empty - contains only spaces or tabs - starts with # - starts with spaces/tabs followed by a #

Edit a script that's somewhere in your path.
Often I need to edit a bash or perl script I've written. I know it's in my path but I don't feel like typing the whole path (or I don't remember the path).

Get rid from a blank display without reboot
Killall5 will kill your session and redirect to login screen. -Very useful when suffering display problems. -Can use F1-F6 -Need to login in the particular console if not already

put command in a loop to keep trying a connection
This will keep trying to reconnect your netcat connection can be used with SSH or Telnet, just substitute nc for ssh or telnet very useful for troubleshooting VPNs were you want to send continuous packets towards a destination to trace.

Create a 5 MB blank file via a seek hole
Similar to the original, but is much faster since it only needs to write the last byte as zero. A diff on testfile and testfile.seek will return that they are the same.

grep -v with multiple patterns.
Use multiple patterns with grep -v. So you can print all lines in a file except those containing the multiple patterns you specify.

Burn an ISO on commandline with wodim instead cdrecord

create an screenshot, upload it to your server via scp and then open that screenshot in firefox
I often need to send screenshots to other people to explain settings and whatever. So I created this oneline which I use to create the screenshot with imagemagik, upload it via scp to my server and then the command opens an firefox tab with the screenshot. The screenshot can be a region or a window. You just have to replace the parts beginning with YOUR.

Control ssh connection
SSH can be controlled trough an ~ escape sequence. Example, to terminate the current ssh connection, type a newline, then the ~ character, and last a . character. This is useful eg when an ssh connection hangs after you reboot a machine and the connection hangs.

Figure out what shell you're running

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