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Dump an aspell dictionary as a word list

Prepend a text to a file.
Syntax: $ prepend content to add [filename] Uses ed, so no temp files created.

remove comments (even those starting with spaces), empty lines (even those containing spaces) in one grep command
useful for discarding even those comments which start with blanks or those empty lines which contain blanks

check open ports without netstat or lsof

Find Duplicate Files (based on MD5 hash) -- For Mac OS X
This works on Mac OS X using the `md5` command instead of `md5sum`, which works similarly, but has a different output format. Note that this only prints the name of the duplicates, not the original file. This is handy because you can add `| xargs rm` to the end of the command to delete all the duplicates while leaving the original.

Non Numeric Check
use to execute a block of code only if $var is numeric

Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

Use colordiff in side-by-side mode, and with automatic column widths.
Barely worth posting because it is so simple, but I use it literally all the time. I was always frustrated by the limitations that a non-gui environment imposes on diff'ing files. This fixes some of those limitations by colourising the output (you'll have to install colordiff, but it is just a wrapper for diff itself), using side-by-side mode for clearer presentation, and of course, the -W parameter, using tput to automatically insert you terminal width. Note that the double quotes aren't necessary if typed into terminal as-is. I included them for safety sake,

Google text-to-speech in local language or language of choice
Google text-to-speech in your local language or in language of choice via country code switch (ISO 639-1).

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.


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