Commands by hkyeakley

Commands by hkyeakley (2)

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Remove blank lines from a file

To save the result, redirect the output to another file. grep -v "^$" file1 > file2
This is sample output - yours may be different.
-1

grep -v "^$" file

hkyeakley · 2009-02-19 18:11:58 3
Quick glance at who's been using your system recently

This command takes the output of the 'last' command, removes empty lines, gets just the first field ($USERNAME), sort the $USERNAMES in reverse order and then gives a summary count of unique matches. Show Sample Output
This is sample output - yours may be different.
```
1 wtmp
      2 reboot
     31 oracle
     15 jsmith
    142 jdoe
      3 root
```
15

last | grep -v "^$" | awk '{ print $1 }' | sort -nr | uniq -c

hkyeakley · 2009-02-18 16:38:59 1

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

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Single use vnc-over-ssh connection

This command 1. SSH into a machine 2. Tunnels VNC port to your local computer ("-L 5900:localhost:5900") 3. Runs a single use vnc server ("x11vnc -safer -localhost -nopw -once -display :0") 4. Goes into the background ("-f") 5. Runs VNC viewer on the local computer connecting to the remote machine via the newly created SSH tunnel ("vinagre localhost:5900")

Split video files using avconv along keyframes

Create a directory and go inside it

$_ expands to the last argument of the last command that was executed

Command for JOHN CONS

Would create a file with a meaningful title. Dedicated to John Cons, who is annoying us users. Merry Christmas!!!

Get all files of particular type (say, PDF) listed on some wegpage (say, example.com)

See man wget if you want linked files and not only those hosted on the website.

List files with full path

Using just globing

Lookup hostname for IP address

A function to output a man page as a pdf file

Tested on Fedora 12. This function will take a man page and convert it to pdf, saving the output to the current working directory. In Gnome, you can then view the output with "gnome-open file.pdf", or your favorite pdf viewer.

Display a wave pattern

Purely frivolous - print a sine/cosine curve to the console - the width varies as it progresses. Ctrl-C to halt.

List files with full path

Using just globing

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