Commands by techie (33)

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Copy from host 1 to host 2 through your host

pretend to be busy in office to enjoy a cup of coffee
Not as taxing on the CPU.

Adhoc tar backup
Creates a quick backup with tar to a remote host over ssh.

Swap a file or dir with quick resotre
This lets you replace a file or directory and quickly revert if something goes wrong. For example, the current version of a website's files are in public_html. Put a new version of the site in public_html~ and execute the command. The names are swapped. If anything goes wrong, execute it again (up arrow or !!).

Watching Command
If you need to keep an eye on a command whose output is changing, use the watch command. For example, to keep an eye on your load average

Using a single sudo to run multiple && arguments
Bash's here string

Remove duplicate rows of an un-sorted file based on a single column
The command (above) will remove any duplicate rows based on the FIRST column of data in an un-sorted file. The '$1' represents a positional parameter. You can change both instances of '$1' in the command to remove duplicates based on a different column, for instance, the third: $ awk '{ if ($3 in stored_lines) x=1; else print; stored_lines[$3]=1 }' infile.txt > outfile.txt Or you can change it to '$0' to base the removal on the whole row: $ awk '{ if ($0 in stored_lines) x=1; else print; stored_lines[$0]=1 }' infile.txt > outfile.txt ** Note: I wouldn't use this on a MASSIVE file, unless you're RAM-rich ;) **

cycle through a 256 colour palette
Rainbow, instead of greys

count of down available ips
avoid wc overload ;)

Find out if a module is installed in perl
Shows the path if the module is installed or exit quietly (to simply avoid the 'No documentation found' msg).


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