UNIX for Dummies Questions & Answers

Hello,
I have an encoded file and I wish to see what is written inside.
The first line is given below:

Code:

eval "$(dd if=$0 bs=1 skip=69 2>/dev/null|gpg -d 2>/dev/null)"; exit

PS: When I google above code, it says that command is use for encryption...
Following lines include many strange chracters in notepad++.
EOT, ETX, STX, SO, FF, DLE, CAN, SOH, etc can be found in lines
Some other characters in that file are:
ȆfÓr⿤µ

I assumed that this is base64 encoded but when I use base64 or hexdump command in terminal it gives some column seperated numbers.

I would appreciate if anybody can lead me to how to make it readable.

Thanks in advance
Boris

If you are using bash:-

help eval

Will tell you what it does.

man dd

Will tell you what dd does.

I don't know 'gpg' so ca't help there.

EOT, ETX, STX, SO, FF, DLE, CAN, SOH look like printer control characters, hex values of 0x00 to 0x1F...

EDIT:

Note that 'eval' is a dangerous command to use unless you know what you are doing...

dd reads from if=$0 one block size of 1 at a time bs=1 starting at the 70th block (skipping 69 characters). $0 is the script name of itself from where this command is issued. It outputs to stdout. The block skipped at the begging is the eval statement.

Take a look at how many characters long that line is, including the newline that it would be in the file.

Code:

echo 'eval "$(dd if=$0 bs=1 skip=69 2>/dev/null|gpg -d 2>/dev/null)"; exit' | wc -c

Code:

69

2>/dev/null is there to not pollute the stdout with the content that is piped to gpg:
gpg -d with the -d flag is to decrypt. In this case, it is not doing it from a filename but from stdin piped from the stdout of dd.
Again, 2>/dev/null will prevent pollution from any warning or status update that it will produce, essentially, disregarding those.