To create two bridged virtual serial ports use the following command:

socat -d -d pty,raw,echo=0 pty,raw,echo=0


The output will show you which are the virtual ports (or pseudo terminals) created, e.g.:

2010/02/19 16:16:33 socat[9662] N PTY is /dev/pts/3
2010/02/19 16:16:33 socat[9662] N PTY is /dev/pts/4
2010/02/19 16:16:33 socat[9662] N starting data transfer loop with FDs [3,3] and [5,5]


Note: if you are using Ubuntu and you do not have this command, try:

sudo apt-get install socat


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Suppose that you want to calculate the space used by all the png files in current directory and all its subdirectories. From a terminal type:

find . -name '*.png' -exec du -ab {} \; | awk '{total+=$0}END{print total}'


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The easiest way I found is dumping the binaries into text files using hexdump and then comparing them with your favourite program (diff, Meld, etc.). E.g.:

hexdump -C a.bin >a.txt
hexdump -C b.bin >b.txt
diff a.txt b.txt


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From a terminal type:

sudo apt-get install xtightvncviewer


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